September Gardening
Things to do in September garden tasks are all about preparing for the change of season, keeping colour and structure alive, and setting your outdoor space up for success next year. September is the perfect month to refresh, tidy, and plan. As the warm days fade and cooler evenings roll in, September is a busy but rewarding month in the garden.
September Garden Jobs
Plant container grown trees and shrubs now while the soil is still warm. This means that the roots can become established before winter sets in and the plants will get off to a flying start in the spring. Because the soil is relatively moist there’s no need to pay much attention to watering, saving you time.
Plant for Spring Colour
September is perfect for planting spring-flowering bulbs such as alliums, daffodils, and crocuses. By planning ahead, you’ll ensure vibrant colour as soon as winter fades. A well-designed garden always has lots of bulbs involved. There are hardly any areas of a garden that bulbs can’t be planted. You can plant bulbs between shrubs or herbaceous plants, in rock gardens or in the lawn. In planning a garden bulbs are a very useful addition to a planting scheme and even if you don’t have a garden they could be put in a pot! One of my favourite jobs this time of year is choosing which varieties to buy for flowering next spring. But with such a bewildering array of varieties available where to start? Some bulbs flower in spring, some are for summer and others flower in the autumn. For now we’ll stick to the spring flowering bulbs, which can be found in garden centres everywhere at this time of year. Aim to buy bulbs that will give a succession of colour from the first snowdrops to the last Alliums in May. Buy your bulbs early. If you wait till later in the season, the bulbs can become damaged or covered in mildew. Don’t buy bulbs that are squashy. They should be hard, like an onion. A rule of thumb when planting bulbs is to plant each bulb twice as deep as its height. If you are buying from a garden centre most bulbs will come with instruction as to the ideal depth, but it can get a little confusing so just remember that the bigger the bulb the deeper into the ground it will need to go. This is because the larger the bulb, the larger the eventual growth will be. Spring flowering bulbs can be planted in drifts, just as they might in the wild, or naturalised in patches among the grasses of the lawn. Whatever the size of your garden, this autumn try planting up a few containers with different varieties of bulbs. By growing bulbs in pots, you can provide temporary colour where they can easily be substituted when they are past their best. For an indoor floral display at Christmas plant some forced hyacinth bulbs specially prepared to flower at Christmas. If you can’t find those, don’t worry, ordinary hyacinths are fine, but will just take a bit longer to flower.
Tulips are a bit of a special case, they can be planted can be planted this month, but it is better to wait until November. For more information on how to create a tulip garden here is a blog I wrote about growing tulips.
If you need help, our garden designers in Berkshire can help you choose bulbs that work beautifully with your existing garden layout, contact us here for more information.
Tidy and Refresh Borders
Now is the time to cut back faded perennials, remove dead stems, and refresh planting beds. A well-maintained border not only looks neat but also reduces pests and diseases. Adding a layer of mulch in September helps retain moisture and protects roots over winter.
September Garden Plants
Dahlias continue to flower exotically. Take off faded flower heads to extend the season through to the first frosts. Cut back to the next side shoot to stimulate new flowers to grow. The best way to extend the season of flowering is to continually dead-head every fading flower from the more tender plants in the garden.
Divide and Replant Perennials
If clumps of perennials have become overcrowded, September is the ideal month to divide and replant them. Doing this rejuvenates plants, improves flowering, and fills any gaps in your garden design. Perennials to lift and divide this time of year include, day lilies, hostas, hardy geranuims, astilbes and ornamental grasses. Leave anything that is flowering at the moment, like asters or sedums until next month.
The Garden in September
Prune Climbing Roses when the flowers start to fade. If they are still growing strong, with lots of flowers, wait until next month. Sometimes it’s hard to distinguish between a climbing rose and a rambling rose. Usually ramblers are the roses that flower only once, normally in June, whereas climbers repeat flower almost all summer. It’s relatively straightforward to prune climbing roses. Using sharp secateurs, firstly remove any dead or diseased wood, then prune all the side shoots from all branches to two or three buds (these will form new growth next year.) If there are new shoots growing from the base, these can be tied in to form the new framework of the plant.
Other Things to do in September Garden
Finish pruning evergreen hedges or topiary, such as yew and box this month. This will give material for semi-ripe cuttings, if you want to increase your stock. Strip off all the leaves and side shoots so that only about 5cm of foliage remains and plant the stem into a container of gritty compost around the edge of a plant pot. Keep on a window sill and water daily until roots have formed when you can plant them up individually. It’s always satisfying to get new plants for free and you can do this with rosemary, lavender, thyme, gooseberries, currants, flowering shrubs and even roses. Another way of getting plants for free is to save seed every year. Sweet peas, nasturtiums, and cosmos are perfect for this and very easy to grow.
Care for the Lawn
Your lawn will benefit from a little attention at this time of year, especially after the long hot summer. Now that we’ve had a little rain, our lawns should be getting greener but will not need frequent mowing for the rest of this year. Aerating, scarifying, and feeding are among the most valuable things to do in September garden maintenance. Remove moss, fill bare patches, and apply an autumn lawn feed to strengthen roots before winter sets in. A healthy lawn makes the perfect backdrop for thoughtful garden design. After mowing, trim the edges of your lawn. This makes a huge difference to the overall appearance and is very simple to do. Use a pair of lawn-edging shears to cut away and long grass that is beginning to encroach into the borders. Ideally you should do this after every mowing but at this time of year, once done, it should stay looking neat and tidy for the colder months ahead.
Harvest and Enjoy
September is also harvest time. Pick apples, pears, beans, and late courgettes, and don’t forget to save seeds for next year. A productive garden is just as much a part of good design as flowers and shrubs.
Make Compost
Now is an excellent time to buy or make a compost bin for all the autumn debris. You can then look forward to adding all that organic matter to the borders to maintain the garden in good heart. Growing plants intensively, as we tend to do, means that a lot of goodness is taken out of the earth in a relatively small area. It is therefore essential to put something back in order to get the best out of the plants. Making your own compost is an ideal way of doing this and I would encourage every gardener to do this. Although there are plenty of bins to buy, I have always found that the best ones are the homemade variety. Remember to use a good mix of different materials to make the best compost. If you grow your own vegetables those alone will generate plenty of material. Don’t use woody stems or diseased leaves, as your compost bin probably won’t get to a high enough temperature to break these down.
Plan Ahead with Garden Design
As evenings draw in, it’s a great moment to think about future projects. Whether you dream of a new patio, modern planting scheme, or a complete redesign, September is the right month to start planning. Our Berkshire garden design company can help transform your ideas into reality.
Your September garden is full of opportunity – from tidying borders and planting bulbs to refreshing your lawn and harvesting crops. A little care this month ensures lasting beauty through autumn and sets the stage for a vibrant spring. If you’re inspired to make bigger changes, our Berkshire garden design team is here to help bring your vision to life. September is the perfect time to plan, prepare, and look forward to enjoying a garden that truly works for you, get in touch and see how we can help.
