Winter sowing is coming to an end, except in sub-tropical areas where the season is only really starting! Time to get ready for winter and the challenges that it brings
Good to know
Combining green manure crops with compost (at planting time) builds long-term organic matter and should supply all the necessary nutrients for the coming season.
- Sow thickly into well-prepared soil and keep the soil damp until plants have germinated.
- No need to thin out because the thicker the cover the better. Till the plants into the soil before they start to flower.
- Some gardeners feed with a compost tea before tilling because it helps the plants decompose faster.
- Let the soil rest for three weeks to allow the plants to decompose, so that nitrogen will be available to the plants.
- Green cover crops replenish the soil with nitrogen, which gets leached out during the season. Mustard and other brassicas act as a biofumigant that is used for the suppression of soil-borne pests and diseases. The plants produce inhibitory chemicals, also known as secondary metabolites, that are released when the plants are tilled into the soil.
- By adding organic content to the soil, green manures stimulate microorganisms, which digest organic matter for use by plants, and keep the soil healthy.
- They improve soil quality, helping to stabilise the soil and prevent run off.
- Plants supply shelter for beneficial insects in winter.
The best time to sow is from March to April, but this can be extended into early May, especially for crops like alfalfa, mustard and buckwheat. Other plants that can be grown as green manures are red and white clover, vetch, black oats, serradella, borage, comfrey, broad beans and peas.
Another way to give your soil a rest is to grow microgreens. These are vegetables harvested when they have 2-3 true leaves, which are used as a garnish or for adding to omelettes, salads, sandwiches, wraps and anything else that catches the imagination. They are grown thickly, like a cover crop, and are obviously quicker to harvest and take a lot less out of the soil than an long crop, like cabbage, broccoli or cauliflower. They can be grown in a sunny bed or in seedling trays. For gardens that become shady in winter, seedling trays are a great option because you just need to find a sunny, sheltered spot for them.
What are microgreens?
Any leafy winter vegetable can be grown as a microgreen. They can be cut when the first true leaves appear or left to form three or four leaves. The smaller the leaves, the better the flavour. Microgreens can be treated as a cut-and-comeagain crop or harvested at once and a new batch sown.
How to grow them
- Like normal vegetables, they grow in full sun, even those in seed trays. Sow microgreens from May through winter, with succession sowing for a constant supply. There are different ways to approach this:
- Broadcast sow a mix of seeds in a bed. Start harvesting after about 10-14 days. Cut daily, based on your needs. If the growth outstrips your need, let some plants grow to baby leaf stage and a few to full maturity.
- Sow by variety in beds, keeping a specific variety to a row so that there is less problem of fast crops outgrowing slower ones. Once a crop of microgreens is harvested, work over the soil, add a little more compost and sow the next batch.
Sow in large seedling trays. Use a seedling mix, pre-fertilise by watering with Nitrosol or Margaret Roberts Organic Supercharger, so that the soil is damp. Sow seed in rows, cover lightly with soil mix, firm it down, water carefully and cover the whole tray with plastic wrap.
Good to know
It’s much easier to practice succession sowing with this method, and you can sow weekly for a non-stop supply.
What’s fun about microgreens is that almost anything goes, and you can choose herbs and vegetables that offer a mix of different colours, texture and flavour.
Try any of these: Amaranth, rocket, basil, basil ‘Dark Opal’, radishes, beetroot, kohlrabi, broccoli, cabbage, kale, Swiss chard, spinach, chervil, coriander, cresses, dill, lettuce mixes (especially oakleaf lettuce), endive, fennel, mizuna, giant red mustard and green peas.