One way to improve yields from your small space is to chose carefully what you grow. Key points to consider when trying to maximise your yield include:
How much of the plant can you eat? Crops like potatoes and courgettes produce lots of inedible leaves, taking up space and energy in your small plot. Salads and stir fry greens are more efficient because you can eat every leaf and shoot. A few vegetables even have edible roots AND edible leaves: radish, mooli and some beetroot, for example. A personal favourite is coriander: the leaves, roots and seeds are ALL edible and all delicious.
How fast does it grow? Slow maturing crops tie up precious container space for long periods. Things like purple sprouting broccoli and brussel sprouts can take 9 months or more. Fast crops include pea shoots (2 or 3 weeks), rocket (5 or 6 weeks), and radishes (3 or 4 weeks).
How long does it crop for? Some veg will produce one crop and that’s it – beetroot and carrots, for example. Others will give you food over several weeks or even months.You can harvest ‘cut and come again’ lettuces over several weeks. Runner beans will give you a supply of beans for two months or more.
How much horizontal space does it take up? Courgettes and potatoes like to spread out, and their leaves take up a lot of space. One way to maximise space is to grow more climbers or tumblers. Productive climbers include runner beans and pole beans. You can also find climbing varieties of courgettes, and some tomato and squash varieties can also be trained to grow vertically. Tumbling varieties include nasturtiums (edible leaves and flowers) and tumbling tomatoes.
And of course what will grow well in your conditions. Tomatoes, peppers and aubergines, for example, will not produce a good yield unless you can give them plenty of sun.
The most productive plants for a limited space (window sills and tiny balconies) include:
- Pea shoots, bean shoots & sunflower shoots.
- Rocket and Japanese salad leaves like mizuna, red giant and mibuna.
- Cut and come again lettuces.
- Radishes – nothing grows easier or faster, and the leaves are edible.
- Herbs like chives, mint and parsley that produce leaves over many months.
And if you have space for a few larger containers on a small balcony or terrace or patio, other productive plants include:
- Runner beans and pole beans – they crop well and heavily over a long season.
- Tomatoes and peppers produce heavy yields if they have enough sun and fertile soil.
Of course there are factors other than just yield for space that will determine what you decide to grow – not least what you enjoy eating! However, unless you love them, here are some crops that you might find hard to make worthwile in a small space:
- Main crop potatoes (early potatoes are better)
- Broad beans
- Artichokes (Jerusalem and globe)
- Cabbages and broccoli
(I’ve also had little success with beetroot. However, as others report this is a good crop for small spaces I’ll keep perservering!)
Good news: there are higher yielding alternatives to some plants in this list. Chinese broccoli produces thick, succulent and delicious stems and is ready to eat in just 7 – 9 weeks. Pea shoots and broad bean shoots make a good substitute for fresh peas and beans. And first early potatoes, while taking up quite a bit of space, mature much quicker than main crop, making a better balcony crop.