My Cabbage Transplants Are Wilting After Planting Out

Cabbage transplants wilting in the first two to three days after planting out is normal and expected — it is called transplant shock or transplant wilt, and it happens because the root system has been disturbed and cannot yet take up water fast enough to supply the substantial leaf area. The outer leaves droop and go slightly limp. If the plants recover overnight and in the morning look better — even if they droop again during the heat of the afternoon — this is normal establishment behaviour and the plants will be fine. The cause for concern is a plant that fails to recover at all over three or more days.

Normal transplant wilt

When brassica transplants are moved from a pot or seedbed to their final position, the roots are invariably disturbed and some root hairs lost. The plant temporarily cannot supply water fast enough to keep the leaves fully turgid in warm conditions. This typically resolves within two to five days as new root growth begins and the root system reconnects with the surrounding soil moisture. Water the transplants in thoroughly at planting — not a sprinkle but a thorough soak that wets the surrounding soil at least 20 cm around each plant. If conditions are very hot and sunny, shading plants for the first two days with a piece of cardboard or shade cloth dramatically reduces wilting stress.

When wilting is more serious

A transplant that does not recover at all overnight, that is still severely wilted on day three and four, or that collapses completely and cannot be recovered by watering, may have: (1) root fly larvae already feeding if eggs were laid near the root zone before planting — check the roots for maggots; (2) a root disease from the seedling compost that prevents establishment; (3) been planted too deep — the stem base below the soil level should not be buried more than the stem depth from the tray; or (4) very severe root damage during transplanting. Plants in these situations rarely recover fully.

Transplanting best practice

Water seedlings thoroughly two hours before transplanting; plant immediately in pre-watered holes; firm the soil around the roots with your fist; water in again after planting. Transplant in the evening or on an overcast day to minimise the first-day heat stress. Do not transplant into very hot, dry, sunny conditions if it can be avoided.