Towards the end of summer and into autumn activity in the vegetable garden slows down as crops are fully grown and their fruit begins to ripen. Winter brassicas are bedded in till spring and the work demands ease off. Apart from tidying the greenhouse and beds, sowing and planting early broad beans there is very little to keep the enthusiastic gardener occupied until the seed catalogues arrive in January.
Many gardeners now move indoors and extend the salad growing season by cultivating microgreens. Microgreens are tender, young green vegetables harvested at the first or second leaf stage and used as a culinary ingredient. They are extremely easy to grow and are becoming increasingly popular.
Because these tiny plants are so young they still contain high reserves of energy and are abundant in valuable nutrients. Researchers at the University of Maryland have found that microgreens have 40 times more nutrient content than their mature counterparts and contain six times more beta carotene and vitamins K, E and C. Microgreens have been used in restaurants for some time as chefs have taken advantage of their intense flavour and rich textures, making them perfect for soups, salads, garnishes and sandwiches.
Technically most plants can be grown as microgreens but the favoured options are from the brassica family. These include cress, a favourite in cucumber or egg sandwiches, mustard, daikon radish, broccoli, cabbage, and any of the oriental salads like pak choi and tatsoi. Basil, dill, beetroot, peas, cilantro, rocket and mizuna can all be grown for their tender foliage.
The seeds are germinated no differently to any other plant, broadcasted generously in a tray of moist seed compost. The intention is to grow a blanket covering of plants that support each other. Cover the seeds with a thin layer of sifted compost and keep moist with a mister, watering daily. Cover the tray with a clear lid to retain heat and moisture until the seeds start to sprout.
After a few days the sprouts will emerge and the cover should be removed. The primary cotyledon leaves will develop as the seedlings continue to grow. A light source should be provided to prevent the seedlings becoming leggy and spindly and potentially damping off, a fungal disease developed in stressful growing conditions. A grow light system is ideal for this and should be height adjusted to provide a constant distance of about 1”/25mm as the plants grow and develop.
After 10-12 days the true leaf develops, this has a noticeably different shape to the cotyledon leaf, and will continue to grow. By the time this true leaf is fully grown and a second leaf begins to form the plant is ready to harvest. Cut a complete section of seedlings at soil level and harvest them in a clump. With only a two week growing period microgreens can be produced all year round, providing an extra vegetable crop whenever needed. They are a tasty companion to most dishes with the healthy benefit of added nutrition.