Jobs to do

Preparing the soil for sowing seed outdoors

It will still be possible to sow seed in mid-autumn, though it should be done within the first week. Seed-beds will therefore need to be prepared; remember that any pre-seeding compound fertilizer or bonemeal to be used should be put on about a week in advance of sowing.

Preparing the soil for planting outdoors

By the time late autumn comes, it is really too late to expect herbaceous perennials to establish successfully before winter and the only planting that can be done will be a few bulbs. However, turf can be. Laid at that time, so the site should be dug over in mid-autumn and prepared as for grass seed, but not to the fine tilth required for seed.

Preparing compost

In the greenhouse some potting of various-sized plants will need to be done, so a supply of potting composts will be necessary. Seed composts will not be required until late winter.

Sowing seed outdoors

There is still just time to sow the hardiest of the annuals and sweetpeas, if done right at the beginning of mid-autumn; they include those suggested for early autumn. It is particularly important that the soil is in good condition when sowing seed now, so that the seed germinates quickly and the seedlings can get themselves well dug in against gales, rain and snow.

Grass seed can still be sown, but the successful establishment of a good lawn from seed sown now depends a great deal on the weather of the next few weeks. If the temperature drops suddenly after sowing, the seed will take most of mid-autumn to germinate, and the seedlings are then very late and grow slowly. If bad weather sets in during late autumn, the result may be large bare patches, interspersed with sparse, weakly-growing seedlings and a good deal of time, money and energy will have been wasted. It is probably best to sow at this time only if you live in a district that continues to be warm until well into late autumn.

Planting outdoors

Although planting the spring-flowering bulbs in early autumn produces earlier flowering and better plants than planting now, such a planting will still give you a good display. In fact, mid-autumn is often regarded by many gardeners as the best time to plant bulbs but, if you dig up a bulb at the beginning of early autumn which has been left in the ground since the spring, you will find that it has already started to push out roots. New growth in the spring-flowering bulbs does start very early after the summer rest and they then go on growing underground all through the winter, except in extreme cold.

Put in the same bulbs as recommended for early autumn, with the addition of tulips and, towards the end of mid-autumn, winter aconites, which produce bright yellow flowers with frills of green in late winter. Iris reticulata planted now will not flower until early spring.

Herbaceous perennials can be planted in those gardens with a light, well-drained soil; newly planted perennials will not do well through the winter in a soil which tends to become waterlogged and may not establish at all. The same advice applies to rock plants and to perennials grown from seed sown in early and mid-summer; such small plants are more safely left in pots or nursery beds until spring and can be removed to shelter or otherwise protected if need be. However, lily-of-the-valley planted now should be successful, provided some grit is added to a heavy soil. It is relatively shallow-rooting, so should not suffer badly from heavy rain; plant it so that the roots are about 5-7.5cm (2-3in) deep, and the points of the crown just above the soil surface. A slightly shaded position is preferred.

The biennials which have been coming on in a nursery bed through the summer can now be planted in their flowering positions. If you are planting a whole bed of one kind, the following spacings will ensure good growth and a good display:

Thinning

Hardy annuals sown outdoors in early autumn will probably need careful thinning by now. You can take the opportunity to weed at the same time, if this has not already been done and clear off any leaves so that the plants are not smothered. As well as being suffocated, they may be eaten by slugs, snails, and other pests sheltering beneath the blanket provided by the leaves and weeds.

Potting

Plants to pot in the greenhouse include the schizanthus pricked out in early autumn, which can now be put into 5-9cm (2 – 3-1/2in) pots, and the calceolarias, cinerarias and primulas sown in early summer, which will either need their final 15 – 17.5cm (6-7in) or a 12.5-15cm (5-6in) size. The late spring-sown cinerarias and Primula malacoides will probably be able to have their final move into 15-17.5cm (6-7in) pots, in which they will flower. Pelargoniums from cuttings may have grown well enough to need a larger, 10cm (4in) pot. Pricked-out cyclamen may have come on sufficiently to need their own pots but they are slower growing and should never be over-potted.

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