Your garden: September 18


French, scarlet runner and butter beans can be sown now in most areas. If late frosts are usual in your area, wait until next month, or start seed under cover for planting out later. Scarlet runners do best when sown in double rows 20cm apart, with 15cm between plants. Growing to a height of 2m to 3m, the plants need a firm framework of wood or steel piping to withstand strong winds.

A bean teepee of strong bamboo or metal enables three or four plants to be grown in a small space. Dwarf beans should be sown in rows 40cm to 60cm apart, with the seeds 8cm apart.

Like beans, sweet corn can be started under cloches. Seed germination is usually rapid and the young plants will grow quickly but should not outgrow the cloches before the weather is warm enough for the shelter to be removed.

Kohlrabi is closely related to turnips and tolerates hotter, drier conditions than white turnips, has greenish-white or purple bulbs and can be harvested from golf-ball size. Celeriac, or turnip-rooted celery, is worth growing for its bulbous roots, which usually are cooked but can also be used in salads. Seed tends to be slow to germinate and sowing in seed trays and planting out when all danger of frost has passed is recommended.

Lettuce, radish, mustard, cress, peas, runner beans, parsnips and carrots can be sown now. White and golden turnip seed can go in too, but sow a small number now and a few more once the plants are well above ground. Turnips are best eaten when just mature or they go stringy, tough and sharp-flavoured.

Leeks and Brussels sprouts can be sown now, as can broccoli and Savoy cabbage.

Seed potatoes can be increased by cutting before planting. Each portion should have two good eyes or sturdy sprouts.

Onions for pickling can be sown.

Sow seed to about twice the depth of the seed. Make the ground firm or the onions will not produce proper bulbs.


Roses respond well to a top-dressing of commercial rose fertiliser or a layer of rotted manure spread around them. Rain will wash nutrients down to the roots. Disbudding may be necessary on vigorous varieties to prevent overcrowding, while shoots crossing over and damaging one another should be pruned.

Dahlias may still be lifted and separated, even if shoots are already above the surface. Divide clumps and if a good shoot is detached from the tuber, don’t throw it out but put it in sandy soil to root.

Hedges can be an attractive feature. To train young plants into a hedge, trim them at least three times a year. The first year’s cut should be severe, to produce plenty of basal growth. Keep the base clear of weeds and grass, or the plants will be inclined to open. Young hedges on poor soil will benefit from a mulch of compost or other manure to feed the roots.

Begonias are one of the more easily grown greenhouse flowers. Tubers that have started to regrow will require repotting if they have already filled smaller pots with roots. Do not water for a day or two after repotting, or the disturbed roots may be swamped with more water than they can absorb.

Potted freesias that have finished flowering can be given less water and left to gradually dry off and put away for the summer to rest in a warm place.

Cyclamen are one of the most popular plants for indoors. Plants that flowered last winter and during the spring will now be declining rapidly. Withhold water gradually until the foliage ripens off.

Pots stored in a shady part of the garden can keep the soil moist enough to keep the corms in good order until late summer.


Strawberries will start to flower in most districts this month. Hand-weeding is the safest method around strawberry plants, which have feeding roots close to the soil surface. A mulch of compost covered in straw or pine needles will feed and protect plants. Remove plants with yellow-edged, colour-streaked or crinkled leaves.


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