September Gardening Tips

Pots & Borders


    • Create a cottage garden effect by sowing easy to grow hardy annuals. Calendula and Love-In-A-Mist [Nigella] look good together. Cornflower, Larkspur and Clarkia will give some height to the middle and back of a border and are good cut flowers too! All can be sown directly into well prepared soil where you want them to flower and don’t need to be raised in trays and transplanted. They are hardy enough to over-winter without frost protection and will give a good show next summer!
    • Check cuttings of Fuchsias, Pelargoniums and other tender perennials for roots. If well rooted, pot them on into 9cm [3.5′] pots filled with good potting compost. If not, leave the potting until spring.
    • Cut back earlier flowering herbaceous perennials close to ground level unless they produce attractive seed heads. The seed heads and some dead stems and leaves can look enchanting with winter ‘haw’ frost on them.
    • Lift, divide and replant the youngest bits of herbaceous perennials that have finished flowering. Most perennials benefit from dividing every 2-3 years. Improve soil and water in well to get them re-established.
    • Replant pots and hanging baskets with autumn, winter and spring flowering and foliage plants. We have masses of choice! Use fresh compost and Osmocote feed for the best results.
    • Take cuttings of Pelargoniums, Fuchsias and other tender plants. Dry off Begonia corms. Cut back and pot up any tender perennials worth keeping in the greenhouse.


Trees, Shrubs, Roses, Conifers, etc.


    • September is the beginning of the traditional autumn planting season and is in fact the best time to plant hardy plants. The soil is moist and warm and plants soon get established now, so get out your spades and get planting!
    • Check roses regularly for black spot and rust fungal diseases. Remove and burn infected leaves and continue regular sprays of fungicide.
    • Make sure that any lavender plants not pruned earlier are done now. Cut off faded flowers with about 2-3 cm of leaf shoot.




    • Plant shady borders and areas under large shrubs with small flowered Crocus, Scilla, Anemone blanda, Snowdrops and Bluebells [don’t plant Spanish bluebells as they may hybridise with our own native bluebells].
    • Try growing a few bulbs, other than the proverbial Hyacinths, in pots for the house. It is much easier than you might imagine! Dwarf Irises aren’t often grown but are very easy if they have good drainage. There are masses of dwarf Tulips and Daffodils to try! Probably the easiest are Tulip ‘Red Riding Hood’ or ‘Pinocchio’. For Daffodils try ‘Tete a tete’ or ‘Jet Fire’. Remember to use bulb fibre rather than potting compost if the pots you use have no drainage holes. Make certain that the bulbs have made plenty of roots and that you can feel the flower bud in the shoot protruding out of the bulb before you bring them into warmth.
    • Pot up prepared Hyacinths to get them in flower for Christmas. Get them potted this month unless you are happy to have them in flower in January.
    • Gladioli corms of the non-hardy type (the majority) should be lifted, dried off and stored in a frost free place. The small corms that form around the base are probably best discarded as they can take several years to reach flowering size.




    • Remove the leading shoot when your greenhouse tomatoes have set five trusses of fruit. This will encourage all the fruit to ripen before late autumn. Regular feeding with a tomato feed like Westlands Grow-Sure will help and also makes the fruit tastier!
    • Take cuttings of border pinks [Dianthus] this month. They root easily, even in a glass of water, and it is a plant that benefits from being regularly rejuvenated by replanting regularly.
    • Check greenhouses for whitefly. They are a little bigger than midges and will fly up in clouds if you disturb them. Hanging yellow sticky pads will trap lots of them but don’t use these if you have introduced or are encouraging natural predators to keep them under control for you. If you have to use chemicals Provado Ultimate Bug Killer is the best available. Always read the label and use chemicals with caution.


Wildlife & Pets


    • Clean out nesting boxes and give your bird table a good scrub before the main bird feeding season gets underway. Jeyes ready to use disinfectant works on bacterial and fungal diseases.
    • Start feeding birds again (if you ever stopped).
    • Provide log piles in odd corners to act as wildlife refuges.
    • Put up Lacewing and Ladybird shelters to provide over wintering refuges for these very useful predators to stay in your garden.
    • Plant or sow native plants. We have a range of natives such as primroses, campion, etc.
    • Install a hedgehog, frog and toad shelter.
    • Leave some seed heads and fruits for winter feed.


Grow Your Own Food


    • Make the first sowing of Vailan – Winter Gem Lettuce now. This greenhouse variety can be grown to produce tasty salads right through the winter if sown regularly and given a little heat.
    • Sow Winter Density lettuce [outside] and the winter mix of Speedy Veg leaf salad leaves too.
    • Plant Spring Cabbages in well prepared soil. Space them 30cm [1ft] apart. Apply a fertiliser that has low nitrogen content, the nitrogen can be added in the New Year.
    • Lift root crops such as carrots and beetroot this month and store them in a frost free place. Bury them in boxes filled with damp sand and keep them in a cool building such as the garage. Setting a mousetrap or two nearby might be a sensible precaution.
    • Lift and store potatoes. They need a frost free dark cool place.
    • Pick ripe Apples and Pears now. If they come off the tree easily without having to tug hard, then they are ready to harvest. If you cut one or two in half look for brown pips to show that they are ready. Varieties harvested now will not store well and should be eaten or cooked straight away. New fruit trees due in this month. Look on our YouTube channel for a helpful video from us on picking and harvesting.
    • Remove and destroy any mummified fruits affected by brown rot. This reduces disease spread from year to year. Fix grease bands to tree trunks to trap wingless winter moths.
    • Plant Garlic cloves now. Light well drained soil suit it best so for heavier soils plant on a ridge of soil that has had plenty of horticultural grit added. Split the bulbs into individual cloves and plant those 20cm [8″] apart. If you plant them close to where you plan to sow carrots next spring, the garlic should reduce the threat of carrot root fly attack on your carrots without resorting to sprays.
    • Harvest marrows, squashes and pumpkins before first frosts. Store in a frost-free shed or garage. Cut them leaving an inch or two of stem attached.
    • Harvest sweet corn when the tassels are just going brown and the tops kernels produce milky sap when a thumbnail is pushed into them.
    • Sow hardy Salad Onions, White Lisbon now. They will over-winter as small plants and provide you with tasty onions for your early spring salads and for flavouring other dishes well before the spring sown ones are ready.
    • Plant winter onion sets and banana shallots for the first crops of next summer.
    • If your peach and nectarine trees suffer from the dreaded peach leaf curl, spray now and again in a month’s time with with a copper based fungicide (such as Bordeaux Mixture). If you can keep the trees dry as the leaves fall off you will also reduce the likelihood of infection from airborne spores that get into the plant through the scars left by leaves as they fall off. This is why peach leaf curl rarely attacks these fruits under glass. Apricots are not attacked.
    • Any trained forms of tree fruits should have the summer pruning completed now.
    • Remove yellowing leaves from the bases of cabbages, cauliflowers, sprouts etc. Sprouts and purple sprouting may need some extra support by staking now.
    • Plant strawberry ‘runners’ (plants). Take care to get the planting depth right! The crown of the plant should be half in and half out of the soil after the soil settles.
    • Sow more Land Cress, Mizuna and Lamb’s Lettuce for winter salads.
    • Autumn fruiting Raspberries should be ready to pick and are so easy to grow! Place your order for fresh virus free canes with us now! (other fruit too).


Lawns, Hedges, Paths and Drives


    • Scarify your lawn to remove old dead grass. Use a spring tine rake and put the old dead grass and moss that you rake out onto the compost heap with some Garotta compost activator. Follow up with a low nitrogen feed such as Westland After-Cut Autumn All In One*.
    • Spike compacted areas of your lawn with a fork and brush in a turf dressing of premixed compost. This particularly applies to well used areas.
    • This is the best month for establishing new lawns. Sow new seed or turf, both after careful soil preparation.
    • Rejuvenate tired looking lawns by over-seeding with a mix of fresh seed and Lawn Dressing compost. This is what professional greens keepers regularly do. You can also use Westland Lawn Thickener [seed and feed]
    • Fast growing hedges such as leylandii will need trimming again and will look better for it throughout winter. Give evergreen hedges a final trim.


Bits & Pieces



Soils, Mulching, Weed Control, etc.


  • Sow surplus areas of your vegetable patch with quick growing ‘green manure’ crop. This will improve the soil structure and reduce nutrients being washed out of your soil by the winter rains. We stock a good range of green manure varieties but if you are in a hurry you could sow mustard which is very fast growing. Dig it all into the soil when it just before it comes into flower.


Ponds and Bog Plants


    • Erect a net over your pond to prevent falling leaves from trees and shrubs getting into the water and increasing the nutrient levels when they breakdown. They may also deprive the fish of oxygen as they decompose.
    • Remove dead leaves from pond plants as they die back.