One of the biggest decisions a gardener has to make can often come before he or she has even started to do any work – what plants to grow.
This goes double for those who are taking advantage of the controlled environment offered by a greenhouse, as this makes it possible to grow species that would not normally be able to survive in the conditions they are faced with.
Indeed, it is even possible to grow some plants out of their natural cycle, if that's something you seriously want to consider.
Growing fruit and vegetables is undoubtedly one of the most popular reasons to get to work in a greenhouse, as this gives you the added satisfaction of using plants you have grown from seed yourself in the cooking process. In other words, there are culinary benefits as well as gardening ones.
Kale is a great choice for such a plant, as it can be very attractive and is also relatively low maintenance. It is a vegetable that is characterised by its green or purple leaves and is closer to wild cabbage than the domesticated forms it also resembles.
It is part of the Brassica oleracea species, which produces a very wide selection of vegetables that are often used in salads or cooking, such as broccoli, cauliflower and brussels sprouts. Acephala – the cultivar group it belongs to – also includes the likes of collard greens and spring greens.
The name is northern European in origin, bearing close resemblance to the Danish word kal, which is used to described many forms of cabbage. Kale can also be known as borecole – and this originates from the Dutch boerenkool, which translates as farmer's cabbage.
Growing kale in a greenhouse is not as difficult as you might think. All you need is the highest standard of potting soil you can find. Kale gets the vast majority of its nutrition from the soil, so it is also worth looking around for a mineral mix to add.
It is important to remember that kale can be very sensitive during its growing process, so try to make sure the plant gets at least 12 hours of light – natural or otherwise. After this, maintenance of the plant is a simple case of keeping it well watered.
Former presenter of television magazine show Gardeners' World and garden writer Alys Fowler underlined the fact that one of the reasons kale is so easy to grow is that it is self-seeding. In an article for UK national newspaper the Guardian, she added that kale can be pretty tough.
"Most kales are hardy and longer-lived than you would expect, easily making it through most winters," the expert commented, adding: "If you want large plants to overwinter, sow in late spring.
"However, you can sow any kale for a cut-and-come-again seedling crop for stir-fries and salad. Sow thinly in situ from now to early autumn and start to cut at five cm high, thinning the plants to 15 cm apart. Pick all winter – if you cloche them, the leaves will remain tender."