Make your greenhouse work harder!
Most people’s greenhouses are used to grow tomatoes, melons and cucumbers in summer, but often an overwintering crop is overlooked. Please reconsider! Could I tempt you to be tucking in to lush winter salad leaves, cos lettuces, radishes, baby turnips or even calabrese and romanesco?
An empty unheated greenhouse is like an enormous cloche ready to be popped over hardier crops. Unlike the soil outdoors, greenhouse beds will still hold sufficient warmth for a wide range of crops to germinate. I’m growing a late crop of summer radishes and some winter lettuce in the greenhouse beds, alongside shallow pots of annual spinach, turnip tops and swiss chard. You could add baby kale, mizuna, wasabi rocket, land cress, corn salad and sorrel to that list. the winter salad that this would collectively create would certainly be impressive!
Potted hardy herbs, too, can be kept in growth. Mint, oregano and chives which often die back in winter would remain in leaf under glass.
Brassicas such as spring cabbage, calabrese and romanesco can, if young plants are transplanted into greenhouse beds now, be cut in early spring. Just keep the spacings slightly wider than normal to encourage good air flow, ventilate on dank days, and avoid waterlogging your soil. A greenhouse is such an investment that it pays to use it for twelve months of the year, not six!