If you want to harvest fresh spring cabbage from your vegetable garden then you need to start planning in summer. Sow your seeds in pots or a seedbed in late July or early August. Aim to have them well grown by planting out time, in October, so that they are large enough to withstand winter weather.
Spring cabbage can be planted out in the vegetable patch once summer crops have been cleared, or into the borders when the summer bedding plants have been removed. You can even grow spring cabbage in containers.
The final size of the plant will depend on the spacing. A 12” spacing will allow the plants to “heart up” and mature fully, while a 6” spacing gives loose-leaved cabbages. If you’re planting in rows you can plant at a higher density, then remove some of the plants as loose-leaved greens in April and leave the others to heart-up in May. Use 4 or 5 plants in a 12” container.
Remember to add some fresh compost or a balanced fertilizer when planting out your spring cabbages, and to feed the plants again in February.
Pests can plague spring cabbages, but simple measures can protect your crop. Covering the plants with fine netting as soon as they have been planted out will protect them from cabbage caterpillars. If this is not possible then the eggs can be rubbed off every couple of days and any remaining caterpillars picked off.
Aphids can be blasted off with a hose. For serious infestations there are many sprays available, including some for organic gardeners, or you can make your own soapy spray.
Cabbage root fly is easily prevented by applying a collar to the base of the stem when planting out. Cabbage root fly collars are available to buy, or you can make your own from a section of carpet underlay or something similar.
If you’ve netted your spring cabbages then pigeons won’t be a problem. If not then you might need to make a bird-scaring device to keep them away.
In windy areas, earth up (mound earth up round the base of the stem) your spring cabbages as they grow, to help prevent root rock. Check to make sure the plants are firmed in after windy weather.
Baby Vegetable Bonus:
You can harvest leaves from your spring cabbages from February onwards. When you come to cut the whole plant, cut just below the head so that you’re leaving a stump in the soil. If you cut a cross into the stump then you will find that it continues to grow new leaves, and that in 4 or 5 weeks you will have 4 baby cabbages ready to harvest.