Hartley Magazine

All the latest news, hints, tips and advice from our experts

Feed and water for bumper harvests

I hope that your greenhouse tomatoes are growing well, despite the lack of light. Itit is time to remove the side shoots of ‘cordon’ varieties, as they appear, using your finger and thumb, to create a single productive stem and channel moisture and energy into fruit rather than leaf. Keep the compost constantly moist, particularly if you are using growing bags, as the compost dries out rapidly; twice a day may be necessary, depending on the weather. Don’t overwater. Erratic watering causes calcium deficiency which appears as ‘blossom end rot’, later in the season, when the end of the fruit furthest away from the stem, collapses and turns black

Outdoor ridge cucumbers can be planted out this month after ‘hardening off’. They benefit from a site that has been enriched with lots of organic matter to help retain food and water and they need plenty of both.

Fill your watering cans with water and allow them to stand in the greenhouse for at least 24 hours to warm up before use. Check your plants regularly as they may need watering two or three times during a hot sunny day; water in the morning or evening and avoid splashing water on the leaves. Regular watering allows your water butt to be replenished whenever it rains and keeps the contents fresh. Seedlings should be watered using tapwater, as the chlorine helps to control fungal diseases and if there is ever a shortage of rainwater, restrict its use to plants that need soft water like citrus fruits.

Growing nicely and ready for potting on into a container one size larger.

Feed Aubergines, tomatoes, peppers, chillies and other fruiting vegetables with high potash fertiliser once a week and pot them on until they reach 28 to 30cm pots. Feed plants on Friday’s, as both begin with F,. If you missed out on sowing fruiting crops like aubergines, it is still not too late to buy plants from the garden centre, though there is less choice and the harvest will be later.

Aubergines and tomatoes can be pollinated by tapping the flowers, ideally when the pollen is dry on a bright sunny day. Allow five or six aubergines to form, on each plant.


Pinch out the growing tip of peppers and chillis when they are about 15cm to encourages branching and heavier cropping and the tips from the main stems of aubergines when they are 30-40cm tall.

It is still not too late to sow sweetcorn in recycled drinking cups with a drainage hole in the base. sow French and runner beans in root trainers and pumpkins in individual pots.

Feed citrus fruits and containerised figs weekly. They can now go outdoors in a sheltered sunny position, ideally against a wall in cooler climates to create space in the greenhouse.

Sow tender herbs like coriander and basil or buy basil from the supermarket divide the clumps and repot into individual pots.  Harvest regularly and feed with general fertiliser to encourage younger, tasty growth, cutting just above a pair of leaves.

Damp down the greenhouse two or three times a day during hot weather, particularly around cucumbers and melons. Tomatoes and aubergines need Mediterranean conditions, so grow them near the door where humidity is lower. Happy gardening, Matt