Friday, 1 March 2024

Asparagus seed saving

I have grown asparagus (Asparagus officinalis) from seed many times.  Growing from sed is fiddly and takes time.  It takes a few years to get a crop when grown from seed, which means that many people prefer to buy year old crowns instead.  

Many heirloom asparagus varieties have a superior flavour and texture, but other than a few varieties nowhere sells plants.  I buy seed of these harder to find heirloom varieties from respected companies, grow them out for a year or two, and sell the dormant crowns.  I don't tend to save seed myself because I cannot ensure pure varieties.  

On average from bought seed I most often tend to get about 30% germination.  Occasionally I get 100% germination, other times I tend to see 10% or frustratingly sometimes even zero percent germination.  I believe this is probably due to the age of the seed, with poor germination from older seed.  

Asparagus seed saving

Asparagus plants are dioecious, individual plants are either male, or they are female.  Unless you pay for some form of genetic testing, you can't tell them apart until they flower.  

Large farms only grow male plants.  If they have any female plants, these will drop seeds, and the seedlings eventually choke the beds making all the plants unprofitable.  

Sadly, home gardeners have been told to remove female plants (due to seedlings) for so long that they think female plants are inferior.  This is not true.  Female asparagus plants are proven to produce longer, fatter, more tender spears.  Home growers probably prefer female plants as they produce longer, fatter, more succulent spears, and many home gardeners can devote the time needed to either remove berries or remove seedlings.  

Asparagus seedlings germinating

Many purple asparagus plants are tetraploid, and many green asparagus varieties are diploid.  I wonder if I could cross them to produce seedless triploids.  If this was the case there would be no reason not to grow female asparagus plants.  I think crossing them may be a project for a future year, or a project for someone else to try.  

Purple asparagus is sweeter than green, and when forced to be white it is even sweeter.  In this country, most of the purple asparagus is from unnamed varieties.  I was buying seed from purple asparagus and growing it out to sell crowns.  Seed is expensive, which meant my plants were expensive.  Buying seed also meant that if the company sells out, or if they send me old seed with low/no germination, I could not grow and sell any plants.  

The past few years I have been unable to buy any purple asparagus seed.  I have a few purple asparagus plants, some are male, others are female.  I decided to allow them to flower, save seed, grow some, and see if the seedings are purple.  If they produce purple seedlings then I can save my own purple asparagus seed.  

Purple asparagus spears

As there are not many pages on the internet explaining how to save asparagus seed I thought I would write a post about how I did this.  

I am only saving seed from purple asparagus because it is not a named variety.  I am not certain that any of the green named varieties will come true from seed.  For this reason any plants I sell from named varieties will be grown from seed bought from reputable companies, and not from seed I saved myself.  

To get seed you need mature asparagus plants.  As mentioned, asparagus plants are either male or female.  You need both in order to get seed, or at the very least you need a female plant and a male nearby that can pollinate it.  

Purple asparagus spear next to green for comparison

Asparagus sends up their spears, they fern out and look nice and fluffy, if the plant is old enough and healthy enough it will flower.  Flowers are uninteresting and small, many insects (and possibly wind) will gladly pollinate them.  

Not long after the flowers die off the female plants will produce little red berries.  Please don't eat these, they are mildly toxic.  I am told that birds can eat them with no ill effects.  The berries turn red and look nice.  

Asparagus berries

asparagus berries

They produce a lot of seed

Once the majority of the berries are ripe like in the photos above, I pick them off the plant.  I hadn't realised before, but some asparagus is slightly thorny after it ferns out, so picking berries can be painful and time consuming.  

The asparagus plants produce tremendous numbers of berries.  I pulled them into a container.  I had planned to collect all of the berries, but there were so many I only collected them from one or two fronds.  

You may notice in the photo that there are a lot of little insects and spiders and things in among the chaff.  I grow everything organically, meaning this is unavoidable.  I left the container for an hour or so while I did something else, this gave time for the tiny critters to climb out and go somewhere else.  

Asparagus produces a lot of seed

Once I had the asparagus berries I could squish a few berries, get their seeds, and I would be good to go.  But what do you do when you have heaps of berries?  

Each berry contains between one and six seeds.  There were many hundreds of berries in my container.  I could not squish each berry and carefully remove the seeds.  

I went through and removed any berries that didn't look ripe.  Anything green was thrown away.  Perhaps the seed would be fine and the seeds would still germinate, but I had enough that I didn't need to risk it.  

I added some water to the container, got a potato masher, and squashed everything.  It made a mess, it smelled bitter (yes, you can smell bitter, if you collect asparagus seed you will know what I mean), most of the fruit pulp floated, while most of the seeds sank.  This made life easier.

Asparagus berries

Once I had enough of mashing asparagus berries, I carefully tipped off  most of the pulp.  Then I added more water, tipped off the pulp.  I did this a few times to remove most of the pulp while retaining most of the seeds.

One thing I was not ready for was that seeds would float after they touched air.  If the seeds touched the air they would get a little bubble, and this would make them float.  If I stirred the mix, the seeds would lose their little bubble, and they would sink.  Some seeds always float, presumably they are not good seeds and they were also tipped off.  

After I tipped off as much water as I could, as well as pouring off the pulp and floating seeds, and left the remaining seeds to dry in the shade for a few days.

asparagus seeds with a little pulp

Asparagus seeds, leave to dry a few days

Once the seeds were dry I put them in a little bag.  There is still a little chaff in there, but that won't affect germination.  

As you can see, I have a lot of asparagus seeds.  I could have collected a lot more seed, but the effort involved is not worth it as the seed loses viability relatively quickly.  This little bag of seeds is now in the fridge.  



From here I had a lot of asparagus seed to plant.  I was curious to see what percentage germinated, and to see if fresh seeds did germinate easily without any stratification or other treatment.

To test the germination rate I got my daughter to count out 100 seeds.  I planted them into a pot of soil and recorded the results.  Not surprisingly, with fresh seed the germination percentage was really high.  No cold stratification was needed, fresh seeds were simple and quick to germinate. 

I really should stop this blog post as it is getting a little long, I will try to write another post on the results of the seed grow out.  

If you are interested in buying year old dormant crowns over winter, or buying some purple asparagus seed, I may list it on my for sale blog page.  


Friday, 23 February 2024

Zolotoe serdtse tomato

This year I grew a tomato called Zolotoe serdtse (золотое сердце), this roughly translates to something along the lines of golden heart, or heart of gold.  I am not entirely certain how to spell this in English, Zolotoe or Zolotoye or Zoloto, I have seen all these spellings used in different places. 

This is a semi determinate tomato variety, that produces very early in the season.  It produces shorter plants, perhaps two feet tall, with regular leaf that are slightly rugrose.  The plant itself looks quite weak compared to many other varieties.  Even though the plant looks weak, it is very productive.

Zolotoe serdtse - persimmon coloured fruits

Zolotoe serdtse is an old commercial variety from Russia, apparently it was bred by Agrifirm Ailita/Aelita.  

I grow a few heirloom Russian tomatoes.  I like old Russian varieties, and I like Russian commercial varieties, often they were bred to be useful rather than to look good.  Often Russian varieties tend to produce well under harsh conditions, and they tend to have a lot of flavour.  

I grow everything organically, so need my plants to have a high level of resistance to pests and diseases, the old Russian tomatoes often have high resistance to pests and disease.  

Zolotoye serdtse tomatoes

Unlike some heirlooms, Zolotoe serdtse doesn't crack.  It is a firmer tomato that does not bruise and seems to store for a remarkably long time.  Many tomatoes I grow cannot even be transported to work when ripe without damage as they are so soft, but this one holds well to transport as its flesh is firm and dense, yet it still stays remarkably tender.  I can't really explain this well.

This tomato has lovely uniform colour.  Unlike many heirlooms it does not have green shoulders.  My camera seemed to have a lot of trouble with the colour, most of the pictures looked too yellow.  

When I put a red tomato, an a yellow jar lid in the field of view the colour seemed to be a lot closer to real life, and stayed like this for a few photos.  In real life they look remarkably similar to persimmons. 

Zolotoe serdtse tomatoes

The fruit is remarkably uniform in colour, but not in size or shape.  Most fruits are about the size of a goose egg, but I realise most people would never have seen a goose egg so this comparison is not useful.  

Probably a more useful comparison would be to say the tomatoes are similar is colour and size to a small persimmon.  They weigh about 80-200 grams each, with most being towards the larger end of this scale.  They are quite beautiful, the colour is uniform throughout the entire fruit.  I really love the colour of these.  

The shape is not entirely uniform, most seemed round and a bit flattened.  This stops them rolling off my bench, while still being large enough and round enough that they are good for slicing.  I quite like the size and shape.  

Zolotoe serdtse fruit size

This year many of my tomato varieties did not produce any fruit, or produced very little fruit, but this one was an exception.  For me it was highly productive, the small plants were covered in loads of beautiful large fruit that looks like persimmons.  While I don't grow tomatoes for looks, these are really beautiful.  

Another thing I liked about Zolotoe serdtse is that it is very disease resistant.  I get a bit of late blight that affects tomatoes here, this variety showed no signs of disease.  I am told that they are cold resistant, and can survive light frosts with minimal damage.  I am also told that they can produce fruit under cold cloudy conditions that would prevent fruit set in most tomato varieties.  This is important to me as it means it will produce for me in cooler years.

In poor soils and with irregular watering, much like many larger tomatoes, it does suffer from blossom end rot.  While frustrating, this can be prevented by regular watering and growing in fertile soils.  Normally the top half of the fruit is unaffected, to the damage can be cut off and the top part still eaten.

Uniform colour the entire way through - my photos don't do justice

The fruit can be a little drier or more dense than most of the varieties I grow, making it great for cooking or for paste.  It also means it can be sliced onto sandwiches in the morning and the bread is not too soggy at lunch time.  I prefer tomatoes with a bit more seeds/gel than Zolotoe serdtse has, but after growing this one I can see the benefits of having a slightly drier tomato with fewer seeds.  

I have read the "medium sized orange golden fruits are superb, meaty and fully-flavoured unlike some other yellow tomatoes".  I agree, they are superb, and meaty, and have considerably more flavour than most yellow tomatoes.  I did find them to have a milder flavour than some tomato varieties I grow. 

They certainly have a richer flavour than anything I can get from the markets, and they taste better than a home grown 'roma'.  People often talk about home grown produce tasting better than store bought, then for some inexplicable reason they tend to plant and grow insipid varieties.  While not the most intensely flavoured tomato I grow, Zolotoe serdtse are probably tastier than most home grown tomatoes that people grow.  

Some of the tomatoes I grew this year

I saved seed from these and plan to grow them again.  They taste good, they produced early, they were very productive, and they look incredible.  

Zolotoe serdtse and Tommy Toe tomatoes

Monday, 19 February 2024

Igloo tomatoes

One of my first attempts at breeding tomatoes is also one of my best.  This project began when I was in high school where I had limited access to germplasm and limited knowledge of genetics and breeding.  

I was aiming to breed a tasty, highly productive, early ripening tomato that did not need much water.  Igloo tomatoes tick all of these boxes and more.  

Igloo tomatoes produce red and round tomatoes, they are small salad size tomato, but large enough to be sliced onto sandwiches.  They are remarkably uniform in size, each weighing slightly under 50 grams.

Igloo tomatoes weight almost 50g each

Igloo tomato plants are stocky compact things only growing to around 1 foot tall, sometimes reaching under 2 feet tall.  Being smaller plants means the space can be used for other things, it also means they are not draining nutrients from the soil merely to produce length of stem.  They do require staking as the amount of fruit they produce is too much even for stout little trunks to hold without some support.  

Being small plants does not mean they are less productive, incredibly Igloo tomatoes are one of the most productive tomatoes I grow.  

Each truss has around 16 flowers, sometimes a few more or a few less.  Each plant produces several hundred red round fruit over the season, for me when crammed in too close to other tomato plants they usually around 12kg of ripe fruit.  This doesn't sound like a lot, but 12 kg of fruit produced on a plant that is only a foot tall and one foot wide is spectacular.  

Igloo tomatoes

For me they are always among the first tomatoes to ripen.  Last time I recorded days, it took 147 days from planting the seed until I picked the first ripe fruit.  This is incredibly quick.  They produce the bulk of fruit before other varieties (including most cherry tomatoes) even start to ripen.  

It is probably best described as semi-determinate.  It does produce a lot of fruit early in the season when no other tomatoes are ripe, and it produces fewer fruits towards the end of the season when many larger and later varieties are ripening.  Even though it is producing less towards the later end of the season, igloo tomatoes always keep producing up until a killing frost.  I have never tried to overwinter them, so don't know how long they can live if protected.

The fruit has a little elbow on the stem, making picking ripe fruit easy an fast.  I think they have the uniform ripening gene, which means the fruit are very evenly red.  I am not a huge fan of the uniform ripening gene, and much prefer fruit with green shoulders, but it was prevalent in the germplasm I had access to at the time I was developing this variety.  

Igloo tomato

Igloo tomatoes never crack or split even if watering is erratic.  I have never had any blossom end rot on these even when other varieties planted next to them are besotted in blossom end rot.  Never cracking, and never succumbing to blossom end rot, means there is not a lot of wasted fruit.

Not only are they among the first to ripen in my garden, they are also one of the few varieties that consistently provide large yields.  Some years the conditions are a bit harsh and other varieties don't really crop, igloo tomatoes always produce about 12 kg of ripe fruit for me.  

Igloo tomatoes produce large seeds, meaning that seed saving is simple.  Larger seeds also tend to remain viable for longer than small seeded varieties.  While seed is always best when relatively fresh, I have grown seed from this that was over 20 years old and had been stored dry in a cupboard.  

igloo tomatoes - not all are ripe enough

I find that these taste ok when not quite ripe enough, but taste great if left to ripen fully.  I tend to allow them to ripen on the plant, but they can be picked early and ripened on the bench.  Like every tomato, they taste best if not put in the fridge.  

I have no idea how well this variety copes with humid coastal conditions, all I know is it performs well for me and produces large amounts of food even with a short growing season.

I have donated seeds of Igloo tomato to a few different community seed saving groups (and encouraged them to distribute the seeds among their members) as it does have the potential to feed a lot of people using a small amount of space.  I hoped to get some feedback about how they perform under different conditions in people's backyards.  Unfortunately I have never heard anything from any of them, and don't know if they have even planted the seeds.  I hope that at least some of them shared the seeds among their members.  

While I am biased because I developed this variety, I think it is a great tomato.  It tastes good, looks nice, provides a huge crop on a small plant, never suffers diseases, ripens early, and is simple to save seeds from.  

If you are interested in buying seed for Igloo tomatoes I list them on my for sale page along with various other vegetable seeds, perennial vegetable plants, and edible herbs.  


Friday, 16 February 2024

Giant Broad Leaf Dandelion

I have been breeding dandelions (Taraxacum officinale) for a few years.  Not just deliberately growing them, but intentionally breeding with the aim of improving them.

Given that every part of this remarkable plant is edible and useful, I mostly focused on breeding for larger leaves.  I also grow pink dandelions (Taraxacum pseudoroseum), I have not done any breeding work with pink dandelions and given how difficult it is to work with them I like never will.  

Giant dandelion leaf 47cm long

Breeding dandelions is difficult, I find it far more difficult than other vegetables.  

The 'flower' on a dandelion plant is hundreds of tiny flowers crammed closely together.  Individual dandelion flowers are tiny.  All parts of the flowers are tiny and are very difficult to work with.  Emasculating flowers to prevent self pollination is difficult as they are tiny, and not always effective as they can produce seeds through apomixis without any pollination.  Due to apomixis, when cross pollinating I have no idea if the cross worked, or if the resultant seed will be a clone of the mother plant.  Adding selective pressure does not always cause genetic drift, again this is due to apomixis.  

Further complicating dandelion breeding is the fact that most dandelions are triploid, and most dandelions in Australia are usually sterile triploids that reproduce by obligate apomixis.  

Unfortunately, while I understand the theory of this, I don't have a good understanding of what this means in practice.  There has been some research into dandelion ploidy and breeding, which I found interesting.  This research indicates that while it should be theoretically impossible to breed using triploid dandelions, it is experimentally possible.  

While there was a concerted effort to breed dandelions, there is very little literature on how to breed dandelions.  Most of this was written by the Soviets, is poorly translated, and largely deals with Taraxacum koksaghyz and breeding it for rubber yield.  

I believe there were a few dandelion farms in Tasmania and Western Australia.  Like much of this country's past, this seems to have been largely forgotten and lost to history.  I wish I could get hold of T koksaghyz, perhaps some day I will track down someone who has seed that they are willing to share with me.  

For these reasons I gave dandelion breeding my best shot, hoped it would work, and figured nothing useful would come of it.  I am happy to say, my breeding efforts yielded impressive results (and at the same time was kind of pointless).

These dandelion leaves grow wide

When starting to breed dandelions I focused mostly on length of leaves as this is simple to measure.  Dandelions produce longer leaves in certain seasons, and under certain growing conditions, so I had to be careful to 'compare apples with apples'. 

Dandelion grow out - leaf comparison

I have a good line in which mature plants consistently produces leaves around 50cm long.  This was a good start.  I considered leaving it there, but my plants weren't as useful as I wanted them to be.  

I had a few plants that produced leaves that were not quite as long, but were wider at certain times of the year.  These are probably more useful as a vegetable.  More leafy and less stalk.  I wondered if I could work with these wider plants, and make them even more useful.  So I (somewhat begrudgingly) did some more breeding work with them.  

Giant dandelion on left, regular dandelion on right

After a lot of fiddly work, most of which yielded exact clones of the parent plant or no seed at all due to rough handling, I started to see some progress.  This encouraged me to do a little more work.  

Again my efforts were largely frustrated by either aborted seed or exact clones of the parent, but among them were some successes.  I am certainly no expert in this area, and my results were patchy at best.  After quite some time my giant edible dandelions are incredible.  

The leaves of my dandelions often measure 6 to 7 inches wide, and are usually a little under 50 cm long.  In winter the leaves are smaller, if they don't have enough water they are smaller, and if shaded they can grow a little larger.  

Dandelion leaf over 6 inches wide

These larger wider leaves are great.  They are far more useable in a salad, or easier to feed to animals.  While I haven't tried it, I assume they could be used to wrap food similar to grape leaves or mulberry leaf. 

I am not keen on how bitter raw dandelion leaves can be, these large broad leaves taste milder and much less bitter.  Dandelion leaves tend to be less bitter before flowering, and become increasingly bitter as the plant flowers.  These giant broad dandelion leaves are pretty mild even when in bloom.  I didn't select for this trait, it was just a nice surprise with the giant plants.  

These plants need more water than lawn weeds if they are to reach their potential.  Regular lawn dandelions don't cope in the dry, these giant broad leaf dandelions really don't cope being very dry.  They tend to survive being dry if they are well established, but the resultant plants are a mere fraction of the size of what they could have been.  

Being so large, these plants need room to grow.  When grown in a pot they are always stunted.  When grown in the garden their roots can penetrate deep in search of nutrients, and they grow far larger.  They survive surprisingly well with competition, but grow a lot larger and faster if you remove their competition.  

I don't think it comes as a surprise to anyone that fertile soil is needed for them to grow large.  Poor soils result in much smaller plants.  

Dandelion leaf over 6 inches wide

These massive dandelions also seem to suffer from a leaf disease from time to time.  This disease produces spots on the leaves, it is possibly some form of leaf rust fungus.  I see this appear on regular dandelions from time to time, but it seems to affect the giant ones far more.  

Dandelion leaf spot

I am sure you could spray with something to control this.  I grow everything organically, so I am not sure how to prevent this disease, all I know is if I leave the infected leaf alone the disease will spread to other leaves.  When I see this disease I remove infected leaves and feed them to the guinea pigs or chickens, this seems to stop it spreading.  

I don't put the infected leaf in the compost for fear it will produce spores and spread, feeding it to an animal seems to destroy the pathogen.  The plant grows replacement leaves and is healthy once the spotty leaf has been removed.  This indicates that the disease is not systemic.  

Dandelion leaves over a foot and a half long

Growing dandelions from seed is simple.  They germinate best when fresh, and germination rates seem to decline quickly as seed ages.  I find light improves germination, so I plant dandelion seed much like lettuce seed.  I plant them in pots or trays of soil, and press seeds into the mix and water in.  From there I treat them the same as I treat lettuce.  

I tend to sow the seeds reasonably thick.  Dandelion seedlings start out small.  I let the seedlings grow a while before transplanting them somewhere in the garden.  Once transplanted, they need a lot of water to become established, other than that I treat them like any vegetable.  

Dandelion seedlings
Dandelion seedlings larger and ready for transplanting

After several years and an absurd amount of effort, I now have good lines of giant dandelions.  They are so large that when people see an individual leaf they often ask me what they are, and do not believe me when I explain they are dandelions.  

I do sell seed of these giant dandelions, as well as pink dandelions, through my for sale page.  The flowers were open pollinated, but there is a good chance they will produce plants that are clones of the mother.  If they were somehow pollinated by another plant, they will have 50% genes from the mother plant and should still grow huge.  If you are interested, everything I have for sale will be listed on my for sale page.  


Monday, 12 February 2024

Mulberry tree for food security

A mulberry tree is like a vegetable garden on a trunk.  

Mulberry trees are well known for producing delicious berries.  What many people do not realise is that mulberry trees also produce abundant and surprisingly nutritious leafy greens.  

I have cooked and eaten mulberry leaves, they taste nice and can be used like spinach or silverbeet.  I have only cooked eaten young leaves.  I imagine older leaves would be too fibrous and I can't imagine raw leaves to taste all that nice.   

Mulberry leaf as a vegetable

While there is little mention of them on the internet, mulberry leaves are eaten as a vegetable in several places such as Cuba and Latin America.    

Mulberry trees produce well with little (or no) irrigation, can thrive in many climates from frosty temperate areas to the tropics, thrive on many different soil types, they have few significant pests, and they produce well on many different soil types.  Mulberries are remarkable trees that are drastically underutilised for food security, they are excellent fodder for livestock, and are a great vegetable for people.  

The taste of cooked mulberry leaves is ok, not bitter or objectionable, but also not remarkable.  I have started to see people sharing recipes using mulberry leaves to wrap lamb or chicken or rice or tofu, similar to how people use grape leaves.  Given how nutritious and abundant they are I think mulberry leaves deserve to be eaten more commonly.

Stuffed mulberry leaves - image from https://maryamsculinarywonders.blogspot.com/2019/04/1234-freekeh-stuffed-mulberry-leaves.html 

Mulberry leaves typically contain more than triple the amount of protein found in many vegetables, and under normal circumstances mulberry trees can produce up to double the amount of protein per acre compared to soy.  

If you don't already have a mulberry tree, you should consider growing one.  Mulberry trees are one of the simplest fruit trees to grow, they grow very fast, and mulberry leaf is the easiest vegetable for beginners to grow and the most productive vegetable for beginners to grow.  

Cutting grown mulberry tree

A study was undertaken comparing the nutritional value of fresh leaves from six different genotypes of mulberry.  Even though there is a bit of a range of values between cultivars it demonstrates that mulberry leaves are far more nutritious than most vegetables we commonly eat.   

I have summarised their findings below:

  • Moisture 71.13 to 76.68% 
  • Protein 4.72 to 9.96% (most vegetables have about 2% or less) 
  • Ash 4.26 to 5.32% (ash is the mineral content: calcium, phosphorus, magnesium, zinc, etc) 
  • Neutral Detergent Fiber 8.15 to 11.32%  
  • Fat 0.64 to 1.51% 
  • Carbohydrates 8.01 to 13.42% 
  • Energy 69 to 86 kcal/100 g 
  • Vitamin C 160 to 280 mg/100 g (oranges have 50 mg)
  • Beta-carotene 10,000 to 14,688 mcg/100 g (carrots have 8,729 mcg)
  • Iron 4.70-10.36 mg/100 g (spinach has 2.6 mg)
  • Zinc 0.22-1.12 mg/100 g 
  • Calcium 380-786 mg/100 g (full fat cow milk has about 120 mg)

Recently a desktop review was conducted comparing several options for households producing all their own protein when there are future disruptions to supply chains.  Their conclusions were unrealistic at best, but they made me think about back yard food production.  

We have a good size vegetable garden, but it is nowhere near large enough to supply our household with all our protein requirements.  We also have a few egg laying chickens, and some fruit trees, including a white mulberry (Morus alba) and a white shahtoot mulberry.  

Following on from the growing protein study linked to above, and given how nutritious mulberry leaves are, I wondered how many mulberry trees I would need to produce all my protein for a year.  So, out of curiosity I crunched some numbers similar to the desktop review.  The results were interesting.  

Mulberry leaf stuffed with chicken - image from https://www.greenprophet.com/2013/05/stuffed-mulberry-leaves-recipe/

A lot of research has been conducted into mulberry tree leaves as they (mulberry leaves, not the berries) are commercially important due to silkworm farming.  I used this research to work out how much protein a mulberry tree can produce, and how many trees would be required for a year supply of protein.  

Often, about 9,600 mulberry trees are grown per hectare or almost 4,000 per acre, this works out to just under one per sqm.  Yields of fresh leaves range from 3.2–21 tons/acre/year (8–52 tons/hectare/year) with most in the 8–12 tons/acre/year (20–30 tons/hectare/year).  This means that on average, each year roughly 2.5kg of leaves are harvested per mulberry tree.  

The protein in mulberry leaves ranges from 15-35% dry weight, or 4.72-9.96% of the fresh weight.  I used 6.5% for the protein content of fresh leaves in my calculations, which is lower than the average.  That works out to 162.5 grams of protein per tree being produced from leaves alone, meaning a one year supply of protein for one person can be provided by the leaves harvested from approximately 112 mulberry trees.   

Mulberry leaves are abundant vegetables

To give this perspective, commercially potatoes yield about 4kg per sqm, providing about 80 grams of protein per sqm.  That’s about 228 sqm of growing area for potatoes per person if relying solely on potatoes to meet protein requirements.  Mulberry trees would only use about 53% of the total land that would be required to grow potatoes and produce the same amount of protein.  As I said earlier, a mulberry tree is like a vegetable garden on a trunk.  

Soy is a legume crop that is known for producing high amounts of protein per acre.  Soy is said to produce up to 513,066 grams of protein per acre.  

Around 4,000 mulberry trees are planted per acre, each yielding 2.5kg of leaves with 6.5% (or more) protein fresh weight.  This produces over 650,000 g protein per acre, which is significantly more protein per acre than soy.  

If growing a mulberry variety with 10% protein in fresh leaves it would produce double the amount of protein that soy can produce per acre.  Mulberry trees produce more protein per acre than soy.  

White mulberry tree outside my back fence 

Comparing the water requirements is a bit more difficult and far less accurate, so you have to take the following 'with a grain of salt'.  

Not surprisingly, I could not find any publications directly comparing the water requirements of mulberry and soy.  According to Agriculture Victoria (https://agriculture.vic.gov.au/crops-and-horticulture/grains-pulses-and-cereals/growing-grains-pulses-and-cereals/growing-soybean-in-victoria), soy requires an average of 2.6 Megaliters of water per acre.  According to the Rural Industries Research and Development (https://agrifutures.com.au/wp-content/uploads/publications/00-056.pdf) mulberry tree plantations require less than 1.3 Megaliters per acre.  

Using the above calculations it appears that mulberry trees could produce about double the amount of protein per acre compared to soy, while using half the irrigation.  Mulberry trees can produce good amounts of protein per acre in marginal areas where soy will not produce any crop because the climate and soils and climate are not right for soy.  

Who knew that mulberry leaves can produce that much much more protein per acre that soy!  

Mulberry cutting

Does all of this mean I am suggesting that people should grow 112 mulberry trees each to produce all their protein needs?  Absolutely not.  

Even though it would be really cool, replacing the lawn with an orchard of heavily coppiced mulberry trees isn’t something that people would want to do.  

While growing this many mulberry trees may be possible in some yards, and would take less time and effort to look after than the average lawn of the same size, I don’t think it is realistic, and I'm not planning on doing that.  

10cm tall to 6 feet tall in under 5 months

I can’t imagine what a miserable existence it would be having to eat about a kilogram of mulberry leaves each and every day to meet your protein requirements.  I don't know what you would do over winter while the deciduous trees are leafless.  

I am not suggesting you plant 2 or 3 mulberry trees, and eat nothing but mulberry leaves for a few weeks each year.  I am also not suggesting that you should grow a mulberry and regularly incorporate its leaves in your meals over the growing months. 

Mulberry leaf plantation
Mulberry leaf plantation. Image by Nahid Hossain, Creative Commons 4.0 license

What I am suggesting is growing a mulberry tree, or several mulberry trees, is a good idea if you have the space.  It will add to your food security even if you never eat the leaves.  

The estimated leaf yields above are based on coppiced trees that are regularly harvested for silkworm production.  When grown like this there are no berries, just leaves.  

Most backyard mulberry trees would not grow like this, most would be allowed to produce berries and develop into large trees with a single trunk or as a multi trunked tree.  As the trees grow larger, they produce increasing yields of both berries and leaves.  

The FAO mentions very old trees in China producing 400kg of berries and 225kg of fresh leaves in a year.  What an incredible sight they must be!  

My mulberry producing food from otherwise unused land

A mulberry tree would increase your food security.  Each year you can eat some berries (they are utterly delicious), or you can grow the tree in your chicken run and let your chickens eat them, if your chickens eat all the berries you will save a little money on chicken feed and help your chickens be a little healthier.  Or you can let the birds take care of them for you.  From time to time the leaves can be eaten, or made into tea, or just left alone to allow the tree to gain energy and grow larger.  

During times of financial hardship, you hear regular stories of vegetable gardens being raided and produce being stolen (and/or destroyed).  While people would probably take some berries, it is unlikely during an emergency that your neighbours would take any leaves from your mulberry tree as they would not recognise them as being edible or as being high in protein and vitamins.  This adds to your food security as you would have a tree full of leaves to cook if you ran low on everything else.  You could use the leaves like spinach, except mulberry leaves are far more nutritious.  

Fresh mulberry leaves can grow large

Chickens and other small animals enjoy eating mulberry leaves.  When hard times hit, you may be unable to buy food for chickens or other little animals .  You certainly don't want them to starve.  The mulberry tree can be used to reduce the amount of bought feed you are using, to get you through until you are able to buy animal feed again.  This also adds to your food security.  

Mulberry trees appear to be the ultimate perennial vegetable.  Most people who have eaten the leaves cooked enjoyed them, some felt neutral about them, so far I have never met anyone who has disliked them.  People tend not to eat mulberry leaves as a vegetable often due to the cultural taboo surrounding eating tree leaves.  For some reason we have been told to view tree leaves as a famine food rather than a sustainable and easy to grow perennial vegetable.  There is nothing wrong with eating healthy organic leaves from mulberry trees.  

Having a nice-looking shade tree in your yard, that is able to provide you with delicious berries in season, and a few handfuls of vegetable leaves if needed, seems like a sensible thing to do.  If you can get past the idea of tree leaves being famine food, all the better! 


Friday, 5 January 2024

Maidenhair fern comparison of varieties

I grow a few different maidenhair ferns, they are lovely ferns and I really like them.  Each type that I grow are noticeably different.  

I sell a few maidenhair ferns each year, and hope they the buyer looks after them.  Sadly, most people think of maidenhair ferns (or any potted plants) like a bunch of flowers: they look great when they buy it and they expect to throw it away after a time.  I am happy to say that these ferns will live for decades if cared for.  

Maidenhair ferns are relatively simple to grow.  I don't mist them or have them under grow lights or make any attempt to control humidity or have a terrarium or anything like that.  I grow some outside under shelter, some in my unheated greenhouse, and some on the bookshelf in the house.  I wrote a previous blog post describing how I grow maidenhair ferns.  

I really like my maiden hair ferns so thought I would make a blog post showing a comparison of the different types I currently grow.  Please note I am not a fern collector, there are many more varieties (as many other species) of maidenhair that exist.  

Variegated maidenhair pinnules are each unique 


Office fern: Adiantum raddianum.  Originally from South America, these are commonly sold in garden shops.  I call it my office fern because it lived on the deak at my office for the first four years that I had it.  People often complain that they had one but killed it because they treated it like a cactus instead of a fern.  It grows long, arching, delicate looking fronds on surprisingly thin black stems.  This fern can get rather dense and vibrant if looked after.  I have had the fern below for almost eight years and it is thriving.  The largest fronds usually reach a little over 50cm long, which is about as big as this one will grow in a pot this size.  

Maidenhair fern - almost eight years old


Chunky maidenhair: probably Adiantum raddianum, but I am not certain.  I was told this is 'Lady Moxon', after growing it for a few years I am pretty sure that it is not Lady Moxon.  It is quite different to my office fern and produces chunky and compact fronds.  The fronds are slightly contorted and twisted, and the pinnules are clumped much closer together than they typical maidenhair ferns.  The stem of each frond is much thicker than normal maidenhair ferns.  I have not grown this as many years as my office fern so it is not as large, and I don't yet know how large it can become.  While it is staying comparatively compact, it seems to be getting longer and chunkier fronds each year.  When I first got this, due to its shape it almost looked similar to a bonsai tree.  

Chunky maidenhair fern
Chunky maidenhair fern

Chunky maidenhair frond

Variegated maidenhair vs chunky 


Variegated maidenhair fern: Adiantum raddianum 'Variegata'.  The elusive and rare variegated maidenhair fern.  Fronds are green splashed with white and produced on thin black stems.  I think there are a few versions of this, but on mine the fronds tend to divide towards the tips.  This is never as large as my office fern, the largest fronds reaching about 40cm long.  My photos never do justice to this incredible fern, it is a delightful and graceful and captivates with its delicate fronds and striking variegation.  

Variegated Maidenhair Fern

Variegated maidenhair frond 


Native maidenhair fern: this is one of Australia's 8 native species, most likely Adiantum aethiopicum but it could be Adiantum capillus-veneris, I really need a fern expert to positively identify it for me one day.  This species is native to Australia, and native to my location.  The pinnules are a different shape to my office fern, and the sporangium are also a different shape.  It is hardier, and survives light frosts and drying out much better than the South American A raddianum.  This sends out runners under the soil, and survives a far wider range of conditions.  This species never gets as dense and full looking as the South American species.  

Australian native maidenhair fern


This is by no means an exhaustive list of maidenhair fern varieties, it is just the varieties I am currently growing.  There are a few other varieties I would like to get some day, but that may or may not ever happen.

I do sell maidenhair ferns from time to time.  When I have a few for sale I list them on my for sale page.  That page has my contact details, so if you are after one of my ferns send me an email and I will let you know if I have any for sale.  If you have any interesting varieties of maidenhair fern let me know, I would love to learn more.