Mid-September has been a real delight with warm, sunny days. I feel we are being lulled into a false sense of security.  The days are becoming shorter, so the next few weeks are going to be busy for gardeners as work has to be done before the soil becomes colder and the wind and rain are more frequent.  On that happy note let’s look at jobs we need to crack on with.

Herbs

Herbs can be kept going over winter.  Dig them up to grow in pots indoors in a greenhouse or a cool windowsill. 

Make sure they have good light and do not overwater them.  This should work with, certainly mint, and parsley, thyme, coriander, sage and oregano.  They will not grow much but they can be then put out again next  year.

Tidy up the Borders

Naturally give the borders a good layer of mulch, but before that clear away Hosta leaves and day lilies and rake up any yellowing foliage.  Tie back any climbing plants as we do tend to suffer with high winds in this area.  Leave some of the more dramatic seedheads such as echinacea and rudbeckia, good for wildlife and look so interesting when there has been a frost. With tender shrubs like salvia leave the stems as this protects the emerging spring growth. Once you have finished weeding mulch the border.  If it has not rained, water it first and then mulch.

Mulching soil  improves the soil’s structure.  Needs about 5cm applying after it has rained.

Compost heaps

Start a compost heap using material cut back from the garden.  Place healthy fallen leaves on the heap, shredding the leaves with a mower helps them break down quicker.  Use a mixture of materials , green material includes, grass clippings, uncooked vegetable peelings. Brown material includes sticks, dried grass, wood chippings and shredded paper and cardboard.  Keep the heap moist but not sodden. 

Turn the heap once or twice in winter but cover it with a tarpaulin or an old piece of carpet to keep the moisture in and your compost may be ready to use in the Spring.

Pick tomatoes and clear vines

It is the end of the season and if you do not clear them now the last of the fruit will rot. The green ones can be put on a windowsill to ripen or put them in a brown paper bag with a banana and some chemical reaction happens to ripen the fruit.

Once all the fruit have been removed you can place the vines in your compost heap.

Perennials: cutting back

Cutting back herbaceous perennials during autumn makes the garden look tidy. But removes  winter interest, in the form of height and structure, as well as reducing the food and habitat sources for wildlife so perhaps be a little more selective by just removing the material that is decaying. Examples of plants to leave uncut include  Eryngium (sea holly) and Phormium (New Zealand flax) and the foliage and flowers of ornamental grasses

More tender plants with woody stems, such as penstemons, are left so that the old stems protect the new growth coming through.  Leave pruning of these and other borderline-hardy perennials until the risk of frost has passed – usually April or May.

Again once you have done your cutting back or tidying up add a layer of mulch 

at least 5cm (2in) thick, applied to the soil surface in late autumn to late winter (Nov-Feb). This provides frost protection and improves plant growth by adding nutrients or increasing organic matter content, reducing water loss from the soil.

Lifting and dividing perennials

This is the perfect time of the year to make more plants by lifting and dividing herbaceous perennials, which are the ones that die back to ground level in the winter and sprout again in spring.

If you have a large clump, dig it out from the border, ensuring you include the root system. Divide the clump using either two forks back-to-back and prising the clump apart and create small groups of plants ready to grow into new plants. Cut off any dead or damaged parts. Plant the groups allowing sufficient room for them to grow. This approach can apply to Astrantia, hardy geranium and helenium.

Deadheading 

Remember to keep deadheading your perennials and shrubs as this allows plants to redirect energy for regrowth so that you can enjoy the flowers they form for at least another month.