I don’t plant many winter vegetables as, to be honest, I like a break from all the hard work of growing food, and I am a bit of a ‘fair weather’ gardener as I do not like to get cold and wet. A lot of my gardening I have learned through being lazy or from trying to save time and money. This winter I learned something new. The last 4 months have been very busy for me and so I neglected harvesting some of my crops. I always leave a few Swiss chard, carrots and leeks in the ground in the hope of harvesting later but usually harvest everything else. Except for one cold spell. this Winter has been quite warm this year. I harvested some beetroot the other day which is a vegetable I don’t really like but I know it is really good for you and so I had some roasted as a side with my meal. OMG it was so sweet and tasted lovely. I also noticed that my spinach, which was in the greenhouse and I thought I had lost when it froze, was actually growing again. I then thought about some of the other crops in my garden that I just leave and cross my fingers that they will be ok and often harvest in February and March when I am running out of fresh produce, and looked into why they taste so nice in Spring. I found out that there is a scientific reason.
There are some vegetables that are tolerant of cool weather but need to be mature by the time the frost hits them. Through photosynthesis these plants produce sugar which they store as starch. When the plant cells freeze they defend themselves by releasing some of the sugar from the starch which helps prevent the frost from damaging them. Unlike the starch the sugar tastes sweet. Tender crops will be killed by a frost, for example, tomatoes, squash, peppers and beans. However I have been growing some of the frost tolerant crops with out realising, including spinach.
Here is a list of some of the vegetables that withstand a frost I may taste sweeter.
Carrots I sow these every year in August and September and in spring I get a crop of smallish carrots that are really sweet. Previously I thought that the sweet taste was because they were quite small (about 3 or 4 inches long) but now I know it is down to the frost.
Beetroot These are best being covered by a fleece as it gets colder but they do get sweeter with cooler temperatures. I had expected to throw mine away when I harvested them this week as the leaves had died but when I dug up the bulb it seemed fine even though I had not protected them.
Leeks I grow in a bucket and a toy box. I need to make sure that the compost does not become solid and so I put them in an area of the garden that is protected by a wall. I use them every spring when I have run out of onions and they improve with a frost.
Lettuce. I grow lettuce in the winter but a variant that is used to being grown in Russia. Any lettuce will be fine if it is grown inside or is only hit by a light frost, which can sometimes make it taste nicer. It is a good idea to cover it with something breathable if you are expecting a harder frost.
Spinach these grow better in cool weather and are likely to bolt when it is warm. They taste so much better after a frost and are full of important nutrients.
Radish these are sweeter when hit by a frost and I cover them with a piece of glass when the hard frosts are around as I grow them in containers.
Broccoli this can survive a cold frost
Brussel sprouts these taste sweeter after a frost. I don’t usually like them and don’t grow them but had some cooked with chestnuts and bacon recently and they were quite sweet.
Cabbages are fine in a light frost but they do not like hard frosts. The frost will improve the taste apparently. I don’t grow cabbages any more as I do not have the room and I can often pick them up quite cheaply.
Kale these prefer a light frost to a hard frost but are a great vegetable to grow in the winter as they are full of nutrients.
Parsley is a herb that I usually harvest and cut back in autumn but I did not get to do it this year. I have noticed that it is still growing this year in January, despite us have quite a few light frosts and a week of heavy frosts.
Cauliflower can tolerate a light frost but is best covered if a frost is expected.
Parsnips it is well known that these taste sweeter after a frost. Some people put them whole into the freezer if there has not been a frost before they use them for their Christmas dinner.
Swiss chard this grows really well in the cold autumn months and I pick it in winter to put into my stir fry. I have noticed that it seems to stop growing for a few months but then has a second wind in spring and produces a lot more stems and becomes larger,
Turnips the bulb and the leaves become sweeter. I grew some turnips for the first time last year and they are still in the ground as they have not grown that big. The leaves are still doing well above the surface and I am going to cover them with a bit of fleece on hooped water pipes this weekend as we are expecting some more cold weather here next week and I will hopefully harvest them in March when I have a gap in fresh produce and when my frozen stocks in the freezer have run down. You can eat the leaves as well as the bulb.
The fact that some of these vegetable do better with a frost means that they are great for lengthening the growing season and are good for planting in spring and autumn. Supermarkets can provide us with most vegetables throughout the year but if you eat them in season some of these vegetables will taste sweeter and nicer and will also be cheaper to buy. If you are protecting crops in the winter by covering them do not use plastic, and try to take off the covers during the day when it is warmer.