Garden News, Tips, Advice and Jobs For September 2024
By Howard Drury
September is finally a better month, after several months in and out of hospital, I am now able to resume bringing you the latest news and jobs for each month. Please do keep revisiting this page for the latest about gardening in September - and fruits are ripening. Dahlias and chrysanthemums should come into full glory, followed by the spectacular display of pinks, mauves and blues from Japanese anemones, asters and Michaelmas daisies. But the days are shortening. There is a nip in the evening air. Heavy dews and the occasional early morning frost are a foretaste of the coming autumn. All this after a pretty rotten Summer dominated by low pressure and below average weather.
As September approaches we are getting signs of high pressure building over the British Isles to bring warm, sunny weather by day and perhaps an Indian summer lasting into October. In other years, the end of September sees much cooler weather and north-easterly winds bring gales and the first widespread ground frosts of the season.
You might consider visiting one of the many autumn gardening and produce shows staged throughout the country this month. You might even consider entering some of your best fruit, veg and flowers in the hope of having your labours recognized with an award or certificate.
News
As Four Oaks trade show approaches we will see lots of announcements of new plants and product which will filter through to retail sales by next spring. Hopefully there will be more news on the peat issues, as yet many of the bark based and timber types composts do not seem according to my trials to be giving the best results. So far, Bathgate Premium Peat Free and Petersfield mixes are giving me the best results, although neither of these are big players in the composts market.
I have become alarmed at some of the silly decisions being forced upon gardeners, so much so, I have started to put together a new presentation entitled Wokeism in Gardening. If you thought my presentation on Climate Change and Gardeners controversial, then this is far much more controversial. Were you aware the RHS has delayed plans for refurbished borders by a year because they found a snail, or why King's Heath Railway station is delayed again by a year! I suppose I had better be prepared to have my bank account closed! Enough said for the moment!
Advice
You may find it necessary to be watering plants if the forecast of high pressure is correct. This is very important with seasonal bedding in containers, which depending on subject, can easily give up once September arrives.
Tips
As many existing retail chemicals will be subject to a gradual withdrawal from sale and use from 1st of October it may be wise to buy now but remember you must use them up or safely dispose of them one year from the ban on sales, garden centres are allowed six months of selling from the ban date.
The Ornamental Garden
The rock garden really needs a tidy and clean up before autumn, and alpines should be given a top-dressing of finely sieved leaf mould and grit. Later in the month, choice plants should be protected from excess moisture by covering them with a sheet of glass. A piece of white plastic tape placed over the edges of the glass will make handling much safer.
Cuttings of alpines, having rooted successfully, can be potted up and kept in the cold frame until spring. You might also consider planting a group of Fritillaria meleagris (snake's head fritillaria) in the rock garden to provide an added attraction in early spring.
In the border, dead heading of flowers continues, and you can make a start on lifting and dividing herbaceous plants, particularly those which flower early in spring. Gladioli will be dying down, but their corms should be left in the ground until next month to give them a chance to mature fully. If you are keen to do some tidying, work can begin on clearing away half-hardy annuals later this month, recycling the old plants on the compost heap.
Michaelmas' daisies and plants with heavy flowers should be provided with plenty of support against the wind if they are to be allowed to display their blooms to best effect. The ties on dahlias should also be checked, and the plants fed fortnightly to encourage the production of good-sized blooms and to help build-up the tubers. Chrysanthemum blooms may be cut as required for arranging or showing, although the plants will still need protection if they are to produce later blooms. If not already done in August, beds for pinks and carnations should be prepared.
The planting of spring bulbs such as crocus, snowdrops, scillas and narcissi, can also commence this month and hardy primulas planted out in large informal drifts if space permits.
Sweet peas can be sown in the open and covered with a cloche, in which case protection from slugs and mice is likely to be necessary. Alternatively, sow the seeds into pots and keep in the cold frame during winter. Sow further hardy annuals to over-winter outside.
At this time of the year shrub cuttings, such as forsythia, berberis, juniper and privet, tend to root quite easily in the cold frame or a sheltered spot in the garden. Water the soil sufficiently to keep it moist, but not too wet.
Continue to remove faded rose blooms and spray against greenfly, black spot and mildew where required and make sure that the long shoots of climbing roses are tied in properly as they tend to be brittle and will easily break in winter weather. You might also consider taking cuttings of mature side shoots from climbers and ramblers, and of this year's growth from hybrid teas and floribundas. Don't forget to post that letter ordering new roses! And with new plants in mind, you could make a start preparing ground for planting trees, hedges and shrubs later in the autumn. New heather beds should also be prepared now, so they are ready for planting in October or November.
In rainy weather it is possible, with care, to move rhododendrons and azaleas during the latter part of September. This is also a good time to move conifers and in order to do so, you need to prepare a root ball of soil which will be carried with the plant as it is moved. The plant should be prepared by driving a spade deep into the ground on two sides of the tree or shrub. A fortnight later, the operation should be repeated on the other two sides. This severs the large roots, but encourages the production of fibrous roots. Conifers are best moved in a wet spell, and once re-planted should be misted daily if the weather turns dry again.
Hedges can be given their final cut for the season during September and the growth of rampant climbers such as clematis, wisteria and ampelopsis can be trimmed back if the plants are taking over the space allocated to them.
Don't forget the fish. They will now require regular feeding because the natural food supplies in the pond become increasingly scarce from this month onwards.
The Lawn
Autumn maintenance tasks can begin, starting with a thorough scarification to remove dead grass and moss. The lawn should also be aerated and a top-dressing of sharp sand or compost applied, working it into the soil and the aeration holes with a brush. Areas of the lawn, which have suffered damage this year, can be repaired by re-seeding or laying fresh turf.
The Vegetable Garden
Floors Castle Vegetable Garden in the Scottish Borders September 2019
Lift maincrop carrots, cutting off the tops as you do so. Split roots should be used as quickly as possible, while others can be stored between layers of sand in seed boxes and kept in a frost-free shed. Beetroot can be stored in the same manner. They should be lifted when they are approximately the size of a cricket ball, and the tops should be twisted off.
In some years, onions can be annoyingly late to ripen. Lifting and placing them on a wire mesh, making sure that the sunlight reaches the bulbs, will assist the ripening process. Ripened onions store best when they have their tops tied in 'ropes' or are placed in single layers in trays. Keep them in an airy place.
Before lifting maincrop potatoes, make sure the skin has 'set' and that it can't be easily rubbed off with your thumb. Allow the tubers to dry for several hours and then store them in wooden boxes in a dark, frost-free shed. Remember to remove all tubers from the soil, however small, to avoid unwanted plants coming up in the wrong place next year.
All outdoor tomatoes and marrows should be gathered in before frost damage occurs, and sweet corn should be picked before the cobs turn too yellow and mealy.
If you haven't already done so, plant spring cabbage now. Early Brussels sprouts may be ready for harvesting. A liquid feed can be given to those plants which are not cropping well.
Continue to earth-up celery and leeks. Leeks will benefit from a feed with a nitrogenous fertiliser.
The Fruit Garden
Complete strawberry planting as soon as possible to give them sufficient time to establish strong crowns.
With the end of fruiting, loganberries will need to be pruned. Cut, to ground level, those canes which have fruited and tie-in and train new canes. Treat blackberries in exactly the same way.
Finish pruning out the old wood on peaches and nectarines.
Gooseberry cuttings can be rooted this month in a light well-drained soil.
Apples and pears should be picked as soon as they ripen. Only unblemished fruit can be stored, and this should be done by carefully wrapping individual fruits in papers and keeping them in a suitable box such as a tomato tray.
September is the last month to order and buy new fruit trees ready for autumn planting, so while you are you chomping on one of this year's delightful varieties, think about the ones you might like to sample in the future. Grease bands should now be placed around fruit trees in the garden.
Grapes can also be helped to ripen. Simply fold back the leaves to expose the fruit to sunlight.
Melons should be cut as soon as they ripen. They can be stored for a few days in a cool larder.
Conservatories, Greenhouses and other Protected Situations
As the strength of the sun lessens this month, so the shading can be removed from the greenhouse and conservatory.
All tender subjects, including fuchsias and geraniums, should now be safely undercover. The top growth of geraniums can be trimmed to about half its length. Trim the roots too; then place into boxes and cover the roots with 2ins of soil. Geraniums should be kept fairly dry throughout the winter.
Check cuttings for signs of mildew and burn any affected plants. Pot-up any which have already rooted. You might also consider taking cuttings of penstemons.
As the month progresses it will be necessary to bring azaleas, cyclamen and solanums in from their summer rest in the garden. The tubers of achimenes should be dried-off by laying the pots on their sides.
Prepared bulbs should be planted into pots without delay, as they will need 8-10 weeks in the dark before being enticed into flower.
Late chrysanthemums should be fed as soon as the buds have formed, and will benefit from having good ventilation and being watered only in the morning. Spray against pests and mildew.
As the month progresses, gradually reduce feeding to all plants except those which are winter-flowering
Wildlife and Nature
To be added
General Maintenance
to be added
Looking Good This Month
Alpines
Convolvulus mauritanicus, Gentiana macaulayi, G. sino-ornata, Linaria pallida, Lithospermum prostratum and varieties, Polygonum vaccinifolium. Spiraea digitata, Viola canadensis, V. cornuta
Bulbs
Colchicum autumnale and varieties, C. speciosum and varieties, Cyclamen hederifolium, Nerine bowdenii, Scilla autumnalis, Sterbergia lutea
Herbaceous
Anemone japonica and varieties, Aster amellus, A. cordifolius, A. novi-belgii and varieties (Michaelmas daisies), Gypsophila paniculata, helianthus,
hemerocallis hybrids, kniphofia, Linum perenne, potentilla hybrids, Sedum spectabile
Shrubs - deciduous
hydrangeas, Potentilla fruticosa, vinca
Shrubs - evergreen
Ericas (including E. stricta, E. tetralix, E. vagans), escallonias,
Climbers
Clematis (including C. calycina, C. coccinea, C. lanuginosa, C. paniculata), lonicera (including L. japonica and varieties)
Trees
Alnus maritima, Arbutus unedo (strawberry tree), Laburnum alpinum autumnale, Sophora japonica
© 27.02.2022 Howard Drury not to be reproduced in any form or manner without the permission of Howard Drury except home use with no commercial gain
