September Gardening Jobs

2. Plant and Transplant Shrubs

Planting shrubs in September gives them a really good chance of getting established. The heat of the summer is mostly passed, and throughout winter, they should get plenty of rain. This helps root growth and means that the plant will be ready to flourish next year.

Here are some shrubs you can plant now:

Cotinus	Also known as the smoke bush, it has deep burgundy leaves and fluffy flower spikes in summer. Will tolerate most conditions in full sun or partial shade.
Hydrangeas	Add a pop of colour and interest to any garden with hydrangeas. Hydrangeas will tolerate full sun to full shade, depending on the variety and most soils.
Ceanothus	A beautiful, blue-flowered plant that can be grown low or trained into a miniature tree. Prefers well-drained soil and full sun.

3. Tend to Drought-stressed Plants

If you have had very little rain in your garden over the past few months, some of your plants may be looking a little worse for wear. Make sure to give them a deep watering, and prune off any damaged material. Apply a thick layer of mulch around the base of the stem; this can be bark or wood chip, compost, or well-rotted manure.

4. Collect Tree and Shrub Seeds to Grow Next Year

Growing your own trees and shrubs from seed is a lot of fun, and now is the perfect time to collect the seeds. You can plant them straight into the ground in an area of well-drained soil, or you can keep them in a cool, dry place and plant them in spring.

Try collecting acorns and conkers, as these are easy to germinate. Hawthorn, rowan, blackthorn, hazel, and lavender are also easy to grow from collected seeds. Remove the seeds from inside the fruit or berries to ensure safe storage.

5. Order Bare-roots for Planting in Winter

Planting bare-root trees and shrubs is a cost-effective way of building a hedge or adding a larger structure to your garden. By ordering now, you’ll get the selection you want and be able to plant them out at the optimal time when they arrive.

September is a great time to prepare your garden for winter and look forward to the spring. Gardening in September can help you to fill your garden the following year without additional cost.

There are still quite a lot of flowers that bloom in September in the UK, including many perennials such as rudbeckias and heleniums, dahlias and nerines. Here we will look further into what to plant in September and other jobs in the flower garden.

1. Flowers to Plant in September

Now is a good time to plant perennials for next year and sow hardy annuals. If you would like to add colour to your garden in October and November, chrysanthemums and asters are good choices and can be planted now.

2. Divide Perennials

One of the most productive September gardening jobs is to lift and divide perennials. This can instantly give you more plants and is easy to do. Make sure to divide perennials according to their individual needs; most can be dug up and then gently teased or cut apart, but it’s important to check so you avoid damaging your plant. Ensure to water in well once you have replanted both.

3. Collect Seeds From Annuals and Perennials

Many annuals and perennials are easy to grow from seed. Allow the seed heads to fully develop so that the seeds are ripe when you collect them. Collect dry seeds where possible or dry them on a paper towel on the windowsill before storing them for winter.

4. Plant Spring Bulbs

September is the start of the planting season for spring bulbs. Planting in September will ensure that they can set out roots before the soil gets too damp; this may help protect them against rotting over winter. Apply a layer of mulch to the soil to add protection to your bulbs against frost.

Here are some bulbs you can plant in September:

Allium	Spectacular pom-pom flowers in a range of sizes and shades of purple, pink and white. Alliums enjoy well-drained soil in full sun.
Crocus	Small but brightly coloured flowers in purples, yellows and whites. Crocus will do well in well-drained and humus-rich soils in full sun or partial shade.
Daffodil	Bright trumpet-like flowers in shades of white and yellow in late winter and spring. Love a sunny spot but will grow in part or dappled shade.
Tulip	Available in a wide range of colours and interesting flower shapes to fit any planting scheme. Tulips like a sunny spot in well-drained soil.
Snowdrop	Delicate white flowers, one of the earliest flowering plants. Snowdrops like rich, moist soils that are well drained and enjoy partial shade. They’re perfect for naturalising under trees.
Grape Hyacinth	Also known as Muscari, these are dainty flower with little spikes of blue or white flowers resembling a bunch of grapes. They will grow in most well-drained soils in full sun or partial shade.

5. Deadhead plants

You can extend the flowering season of many plants by deadheading them regularly. Leave the flowers on hydrangeas now, as they help protect the plants from frost damage.

6. Cut Back Perennials

Some perennials will be beginning to lose their vigour in September. If they are looking a little tired and are not going to provide winter interest or food for birds, you can cut the flowers and foliage down to the ground.

Take the opportunity to do some general maintenance in September before we head into winter. This will help carry your garden through any bad weather and fill it with life next year.

1. Remove and Dispose of Dead Leaves

Rake and compost dead leaves that could provide habitat for pests in your garden or create problems for other plants. Allow leaves to fall under hardy shrubs, as they will provide mulch for the plants. Fallen leaves can also be collected to make leaf mould, which is ideal for sowing seeds.

2. Mow the Lawn but Raise the Cutting Height

Prepare your lawn for winter by continuing to mow the grass, but remember to raise the cutting height of your mower to keep your grass thick and healthy.

3. Scarify, Aerate and Fertilise Your Lawn

Another way to prepare your lawn for winter is to scarify, aerate and fertilise it now whilst growth is still quite strong. If your soil is hard and compacted or water pools on the surface during winter, this is a sign that your lawn needs aerating. Scarifying can help manage moss, thatch and dry material. Applying fertiliser to your lawn in September can help prepare it for the harsh conditions of winter.

4. Cover Ponds with Netting

Covering a pond with netting can stop falling leaves from clogging it up, unbalancing nutrients over winter and causing the water to get cloudy and dirty. By covering your pond in September, you will prevent this. Ensure that any nets in the garden are secure, as they may otherwise present a hazard to birds.

5. Clean Out Bird Feeders

Feeding birds in our garden over winter is really important and we suggest going into the season with clean bird feeders. Dispose of any uneaten seed that might be going mouldy and refill with fresh seeds or nuts.

As the year progresses, the pests and diseases we see in our garden begin to change. Be aware of them but remember that the best defence is a well-balanced ecosystem.

1. Powdery mildew

Powdery mildew is a common fungal infection causing leaves and stems to look greyish. This can interrupt photosynthesis and weaken the plant. There is no cure for Powdery Mildew, but you can slow its spread by removing and disposing of the affected material. Prune to increase airflow around affected plants, and ensure that if you are watering, you are doing so directly to the base of the plant.

2. Honey Fungus

Honey fungus is one of the few fungi that are not beneficial to our plants. It attacks and kills the roots of plants and then breaks down the dying wood. Very few plants are safe from Honey Fungus. To check if your plant is suffering from honey fungus, peel back a small section of bark near the ground. Honey fungus will show up as a thin white layer between the trunk and the bark. There are no treatments for Honey Fungus; the only remedy is to remove the plant entirely.

3. Vine weevil

Vine Weevil can affect hedges, trees, and shrubs. The adult is a small blackish-brown textured beetle with an elongated head. They eat foliage leaving small, irregular-shaped holes and notches in leaves. However, the grubs are far more damaging, eating large portions of plant roots. September is a good time to apply a nematode treatment to your garden to help control Vine Weevil populations. However, the best control for vine weevils is to create a wildlife-friendly garden, encouraging their predators, such as birds, ground beetles, hedgehogs, frogs, and toads.

We hope you’ve enjoyed our gardening tips for September.

Want to get ahead on your to do list? Find out what you can do in your garden in October here.