Mildews are encouraged by autumn weather but so are lawns, especially if dethatched and fed.
Bulbs go in with ease if you have the right tools. Indoors, surplus fruit and vegetables can be preserved for winter and houseplants shifted to winter positions.
1 — Mildews
Dewy warm nights and autumn rains promote powdery, downy mildews and botrytis (grey mould). No fungicides are available for downy mildew or botrytis, but removing infected growth and thinning and pruning plants to enhance airflow helps. Powdery mildew fungicides are available for ornamental plants, but their use is not often worthwhile this late in the year; instead, gather crops such as squash from affected plants or cut back flowers such as delphinium or lupins – regrowth is usually unaffected.
2 — Thatch
Dead roots, stems, moss and vegetable matter mat together at the base of lawns, creating a thatch that inhibits water and nutrient penetration. Some thatch can be helpful, but if thicker than 1cm, it can make the grass unhealthy. Removing excess thatch by raking in early autumn allows for better, thicker grass growth before winter, particularly if lawn feed and top-dressing are subsequently applied.
3 — Tools for planting bulbs
Even after autumn rains soften the soil, planting bulbs can be strenuous. Loosening soil by inserting a fork and levering it back makes using trowels much easier. Gently tread the soil back afters without stamping, which can crush bulbs. Long-handled bulb-planters are good for small bulbs, and save your back, but when planting larger bulbs, which may need to be planted 25cm deep or more, use a planting or border spade.
4 — Glut
Vegetables and fruit come in with a rush in September and there can be wastage. Happily, preservation can be applied to most crops – piccalilli uses up surplus beans and cauliflowers, oversized courgettes and cucumbers and undersized onions. Green tomato chutney and runner-bean chutney are mainstays of preserving, but apples, beetroot marrows, rhubarb, and tomatillos can also be used.
5 — Houseplant changes
Feeding houseplants can end now that the main growing season is over. Those growing outdoors should come inside before frosts arrive, after removing any woodlice, and drenching with nematodes against vine weevil. Move shade-loving plants to brighter places. On mild days, take dusty plants outdoors and wash with lukewarm water – the dust hinders scarce winter light.
Guy Barter is chief horticultural adviser for the Royal Horticultural Society (@GuyBarter).
The Royal Horticultural Society is a charity working to share the best in gardening and make the UK a greener place. Find out more at rhs.org.uk.