September Gardening Jobs

Now that September is here, it feels a bit cooler and breezier than last month. It's a good time to start getting your garden ready for autumn and winter. As weather can vary, treat the advice below as weather-dependent and avoid treatments during extreme heat or frost.

General tasks

September is a busy month in the garden. If you’re not familiar with the general upkeep, here are the must-dos.

• Control weeds: Keep them at bay with the right weed control solution. If pets use your garden, choose a product that allows them to return once the area is dry.
• Continue to water: Even when it isn’t hot, water plants and grass as needed, especially in warm spells.
• Clear away autumn debris: Leaves and twigs start to fall now. Regularly sweep up to keep your lawn tidy and healthy.
• Plant spring flowering bulbs: Get tulips and narcissi in the ground this month.

What should I do to my lawn in September?

Even if you use the garden less as the nights draw in, your lawn still needs attention. Focus on the essentials below.

1. Scarify and remove moss: Remove thatch, moss and debris so the lawn can breathe. A spring-tine rake works for small areas. For larger lawns, a scarifier is worth it. For moss-heavy lawns, consider A1 Lawn Double Strength Feed, Weed & Moss Killer. For heavy patches, Maxicrop No.2 Moss Killer and Lawn Conditioner or MossOff Chemical-Free Moss Control are also popular.

2. Overseeding Season: Warm soil and more frequent rainfall make September ideal for overseeding. It thickens the sward, repairs worn patches and improves resilience against weeds and moss. Our best-selling seeds for September include:

• A1 Lawn – Premiership Pro Grass Seed – ideal for a lush, premium-quality finish.
• A1 Lawn – Shade & Drought Grass Seed – perfect for tricky areas under trees or in dry spots.
• A1 Lawn – Luxury Hard Wearing Grass Seed – designed for lawns that see plenty of foot traffic.

3. Apply an autumn fertiliser: An autumn feed strengthens roots and helps the lawn face colder months. It reduces stress, encourages root growth and improves disease resistance. Our top pick is:

• A1 Lawn Ultimate Autumn Winter Lawn Fertiliser

If you’re sowing new grass, start with A1 Lawn New Grass Pre-Seed & Pre-Turf Fertiliser to give seedlings the best start. For ongoing lawn health, liquid options like A1Lawn Ultimate Lawn Seaweed Extract also provide a natural boost.

What should I prune in September?

Autumn is a sensible time to shape trees, hedges and shrubs. Clean, sharp cuts reduce disease risk and minimise debris blowing onto the lawn.

Autumn pruning checklist:

• Roses
• Fruit bushes
• Flowering and hardy shrubs
• Deciduous and ornamental trees
• Perennial flowering plants (except those with decorative seed heads for wildlife)

How do you prepare flower beds and border plants for autumn?

• Deadhead faded flowers: Keeps displays going through the month.
• Apply mulch: Compost helps retain moisture and tidies the bed.
• Remove or protect non-hardy plants: Some perennials struggle in frost.

Perennials vulnerable to frost include:

• Tender perennials such as geraniums
• Herbaceous perennials such as peonies
• Annuals such as marigolds
• Flower bed plants such as begonias
• Subtropicals such as palms, bougainvillea and lemon trees

If a freeze is forecast, bring them indoors, use horticultural fleece, or lift and store.

September is about preparing for autumn. By scarifying, overseeding, fertilising and tackling weeds now, you set up a stronger lawn for spring. As we move into October, focus turns to frost protection, planting trees and shrubs, and continued lawn care. Read our October gardening jobs next.