Wednesday, 2 December 2015

Overwintering vegetable plants

We have some perennial vegetables which I decided to overwinter.  We moved in Spring so I have not had time to make a post about them until now.  We had the coldest winter since we have lived here and lost a lot of frost tender plants that I normally can overwinter with no effort.  I took a few pictures of some of the survivors.  Most of these plants are far larger now.

Kangkong (Ipomoea aquatica)

This is a heat loving tropical perennial leaf vegetable which is often grown as an annual in cooler climates.  It grows well from seed, but I wanted to see if overwintered plants were larger than seed grown and it appears that they are.  It has many common names and is related to sweet potatoes.  I am not overly fond of leaf vegetables, but I like kang kong.  Unlike many other leaf vegetables it never goes bitter, it can be eaten raw or cooked.  I have only eaten it raw and it tastes nice, apparently cooked it tastes a lot like spinach.

I grew it in too small a pot so it did not reach anywhere near its potential last summer.  I tried to grow it in a fish talk as a floating water plant but there was not enough sunlight and it appears to prefer at least some soil for its roots.  It tried to flower but then winter came and the cold cut it down to a stump.  I do not want to save and plant seed each year if there is an easier way and this plant grows easily from cuttings.  I am glad that this can be overwintered as it is simple and the plants are larger than seed grown.

Once the warmer weather came along it started to grow fast again.  I wish I knew about this plant years ago as it is great.  It dislikes the cold weather and dies back badly even without frosts but survives and grows very fast once the days are warm.
Kangkong resprouting in late winter, it dislikes the cold air even when protected from frosts
The same plant in Spring after being cut back a few times
Chilli - Trinidad Scorpion Butch T
Most varieties of chilli available to home gardeners can be overwintered easily enough.  Super hot chilli are a lot more finicky than regular chilli and capsicums from what I have heard.  Being the first time I have grown the super hot chilli I decided to try and overwinter it rather than start from seed again.  Strangely it went very well and was very easy.  I tried to keep it out of the frost at night and put it in the sun during the day when I remembered.  I accidentally let it get a bit of frost a few times and forgot to put in in the sun more often than I remembered and all three survived nicely.
Trinidad Scorpion Butch T in tiny pot
Super hot chilli in late winter - not many leaves
Strangely healthy chilli in winter
The same plants after the weather got warmer
Trinidad Scorpion Butch T
Indeterminate tomatoes
Most indeterminate tomatoes are simple to overwinter if the frost can be kept off them.  This year was colder than most and I lost most of the tomatoes I had planned to overwinter as I did not look after them all that well.  I grew one seedling far too late  in the season last year so decided to try and overwinter it.  Mid winter, with no heat, just moving it inside at night to avoid frosts the plant started to flower.  The flowers all fell off as it was too cold for pollination to occur but the plant was mature.  This meant that it is easy to plant them out when the weather warms and have them set fruit almost right away.
Tomato plant mid winter
Micro Tom tomatoes
Micro tom is a great little tomato variety that needs more people to grow it and save its seed.  I grew one on the kitchen window over winter to see how it would go.  Apparently they grow just fine over winter if kept inside and this one started to flower when the nights were still frosty outside.  They have such a short lifespan that this particular plant flowered, set fruit and died before Spring came.  What a great plant, while it may not be the tastiest tomato variety it was a lot better than any cherry tomato I could buy from the supermarket at that time if year.  They are not terribly productive but being so small means that it can grow in a tiny pot and not need much space to provide a crop.  Being able to bring them indoors at night means that it is possible to get them to set fruit in Winter, I never would have thought that getting fruit in Winter was possible for a tomato that is not parthenocarpic.

I also planted some Micro Tom seeds mid winter to see if they would germinate in the cold and they did.  Being such tiny plants the kids adore them.  They are even more happy to eat the tomatoes and they tend to carry the tiny plants around talking to them and treating them like pets rather than plants.  The more I grow Micro Tom the more I discover about them that shows me how good they are.
Micro Tom tomato flowering in mid winter
Vietnamese Coriander (Persicaria odorata)
This perennial herb has many, many common names.  It smells a lot like coriander and is far simpler to grow.  It does not bolt to seed like real coriander and does not even flower often outside of the tropics.  It appears to love water and I grow it as a bog plant or an emergent water plant.  It does not like frost, mine got frosted a few times but they all came back in the warmer weather.  Over winter they look terrible, as soon as the warmer weather returned they sprang back to life.  Cuttings strike very easily in water so once it warmed up I cut one plant into many pieces, the original plant grew back and each cutting grew roots within a few days.
Vietnamese coriander leaves turn a bit red in cool weather
Water Celery (Oenanthe javanica)
This is another emergent water vegetable, it is grown for leaves and stems that taste of celery or parsley.  Like many of the vegetables I grow this is a perennial vegetable that rarely flowers or sets seed.  I have the variegated form of this vegetable, while it is prettier than the regular green one it is also not as aggressive in its growth.  I would like to track down the regular green version one day and see just how strong it will grow.  I would prefer a productive vegetable to a pretty vegetable.

My plant grew with no winter protection, the top of the water was covered in ice many times.  It certainly did not love being covered in ice and died back somewhat, the smaller plants that were grown with protection from frost looked a lot healthier at the end of winter.  As soon as the heat returned it was very fast to recover.

Water Celery surviving winter with no protection.
Where to get perennial Vegetables
I have been selling perennial vegetable plants and some seeds for years.  Unfortunately we recently moved to town and do not have any land so will not be selling anything for a while.  We do plan on moving again very soon, when we have settled I hope to sell perennial vegetables and vegetable seeds again, they will be listed on my For Sale page when the time comes.


  1. I overwintered two tomatoes, one jaune flamme left in the garden in a protected spot, the other a cutting I took from a 'volunteer' seedling at the end of summer. The cutting did really well, protected in my glasshouse, and I'm getting reasonable-sized tomatoes from it, but the bother of it all is that I don't like the taste! Not sure if it's because of the fruit growing late winter and spring, or whether the seed that grew was just a horrible supermarket tomato. The other one, the jaune flamme, left to struggle in the open, has been producing nice tasty fruit for a couple of weeks - not many - but the plant itself looks sick. I've heaped home compost around it and watered it with Charlie Carp to see if the plant produces more leafy growth. It's fun experimenting.

  2. Hi Parlance,

    I think you are doing pretty well getting ripe tomatoes before Christmas!

    I agree, it is a heap of fun experimenting. I find it interesting what I can actually achieve if I put in the time. I have developed a few varieties of vegetables and been able to grow many things that people said were not possible. If I had the time and space to grow out a lot of vegetables I wonder what I could actually produce.