August allotment garden

Last revised: 01 March 2018

Seasonal reminders, hints and tips.

Show time

Jubilee Road Late Summer Show is set for mid-September, make sure your preparations are well in hand having identified the crops and plants most likely to be ready for show. Read more about our show, and hints for entering

Prepare your entries and entry form.

Local shows

One of the premier fruit, flower and vegetable shows in Middlesex is led by the "Federation of Middlesex Horticultural and Allotment Societies". This years show (2019) will be open to public from 2.30pm on 15th September at Perivale Community Centre. Entrance if free. The show is worth a look to see how to present competition entries, which is just as important as quality. Prepare to be amazed.

Seasonal hints and tips

Potato and tomato blight

Please read this article about Potato and Tomato Blight which is likely prevalent now on your crops or those nearby.

Remove infected leaves and stalks, and dispose at Council green recycling centre.

Late sowing

Start lettuce and beetroot under glass or indoors to get rapid growth. When plants are large enough, plant them out.

Sowing for winter

Spring cabbage is commonly sown from seed during June and July to overwinter and provide fresh greens from February. It is time to put out the young plants, or you may get decent growth by sowing before end of August. As you clear patches of ground there are some good alternatives to consider.

Broccoli Rabe or rapini is smaller, spicier and faster growing than main crop broccoli. A member of the turnip family and the stalks, leaves and flowers are edible.

Kale provides an easy to grow green vegetable that will usually provide picking until March.

Swiss chard and perpetual spinach are productive through autumn and winter months as they enable picking leaves and stalks without digging up the plant.

There are certain varieties of autumn onions available as sets which are hardy for winter and will be ready to lift in June or July.

Salad leaves like wasabi, mizuna and mustards are less prone to bolting when sown as a winter crop and are hardy enough to last through to spring.

Some swede and radish varieties are suitable to stand in the ground through autumn and winter. The globes may be smaller, though generally sweeter with more zing.

Christmas Potatoes

Some gardeners have been successfully planting potatoes during August in very large pots, grow bags or raised beds. This method usually allows first or second early varieties to mature for a crop in December ( 12 to 14 weeks).

Plant 2 or 3 seed potatoes in the container on 10cm of soil and cover with further 20cm compost and soil mix. As plants grow cover the haulms with more soil until at top of pot or 40 to 50cm deep.

Keep in a warm place, full sun and moist, not soaked. If kept outside use fleece to protect leaf and maintain warmth.


Onions are usually ready for harvest now. A sure sign is the stalks falling over and dying off.

To harvest, lift the onions, remove dirt and lay out in the sun or in dry place to dry the stalks and bulbs over next few days.

Examine bottom of bulbs for mildew and separate these from the main crop. If they are not soft, use these first. The soft bulbs should be disposed at the Council green recycling centre. Do not add diseased or soft onions to the compost as this spreads the mildew.


The tall plants, like sprouts, are subject to wind rock which will loosen the roots. Earth up the plants and firm around the root area. You may wish to stake the plants to provide more support in high wind. Take time to remove dead leaves and as many caterpillars, slugs and snails you can find.

Brassica pests

Cabbage white moth is the main pest which, despite the name, will lay eggs on any brassica. The eggs are tiny, laid in clusters, very hard to spot and develop over 2 or 3 days into voracious caterpillar.

One technique uses sticky tape wrapped around a hand with the sticky side facing outward. Palm undersides of leaves you suspect being infested with aphids, eggs or caterpillar. An old sponge on a stick or pan cleaner wrapped in tape is convenient.


Strawberry plants rarely do well after 3 years. Prepare new plants for next year by cutting off runners that are nearest the parent plant, and planting the plantlets in posts or new location. Remove other shoots from the parent to direct energy to itself.


The best fruit will grow on young wood that sprouted last year. A way to take this years crop and prune the plant is to cut the whole branch near ground level and pick off the fruit afterwards. Leave new shoots to grow and thin these out later in the year. When all the crop has been taken, feed the plant at the roots with either a well rotted manure or liquid feed.