Annual spinach is more inclined to bolt than perpetual spinach but it’s far tastier. Tender spinach leaves are a wonderful addition to salads. Spinach is very good for you and cooked properly can be very tasty. The bolting problem is caused by warm, dry weather – it will fare much better in cool, damp conditions.
Given its propensity to bolt, succession sowing is the key if you want a constant supply of spinach during the season. Sow in module trays, 1.5 cm deep every three weeks from April to August. Sow three or four seeds in each module. You can also sow direct in the soil outside if you wish, but slugs can be a problem as the tiny seedlings are getting established.
Transplant to final growing spot, leaving 25cm between rows and 7-15cm between plants (depending on whether you want baby leaves or regular ones). Spinach can be grown pretty much anywhere and doesn’t need to be inluded in your rotation – use it as a flexible filler and for intercropping. Summer sowings should be done in partial shade to prevent bolting. Water copiously particularly in summer – as soon as the plant dries out, it will bolt. Apply an organic liquid feed (nettle is good – high in nitrogen) if growth seems lacklustre.
Spinach will be ready to harvest 8-10 weeks after sowing. Take the outer leaves first. You can also cut the entire head off at ground level – it will sprout new leaves and you will be able to crop again in a few weeks.
Bolting – annual spinach is far more interested in reproducing (producing flowers and seeds) than it is in producing leaves that you can eat. You may need to net seedlings from birds. Downy mildew can be an issue – it will manifest as white fluffy patches on leaves – prevent this by giving plants plenty of space.