What to Do in the Garden in September

September brings a gentle shift from summer to autumn. The harvest continues, but it's time to start preparing for the colder months - planting bulbs, moving tender plants indoors, and enjoying the last of the summer colour.

Key Takeaways for September

• Plant spring-flowering bulbs
• Continue harvesting summer crops
• Move tender plants indoors before frost
• Sow winter salads and hardy annuals
• Start lawn renovation
• Divide perennials while soil is still warm

Flowers

Autumn brings its own beauty with asters, sedums and late dahlias. Start preparing for spring.

September Flower Tasks

• Plant daffodils, crocuses and other spring bulbs
• Divide herbaceous perennials while soil is warm
• Take cuttings from tender perennials like fuchsias
• Lift and store dahlia tubers after first frost blackens foliage
• Collect seeds from favourite flowers
• Move tender plants indoors before first frost
• Plant winter and spring bedding
• Cut back spent perennials
• Sow hardy annuals for early flowers next year
• Plant container bulbs for spring display

Fruit and Vegetables

Autumn harvests continue with apples, pears and late vegetables. Clear spent crops and prepare for winter.

September Fruit and Veg Tasks

• Harvest apples, pears, plums and autumn raspberries
• Pick squash and pumpkins before frost
• Lift and store potatoes before they rot
• Continue harvesting tomatoes and beans
• Sow green manures on empty beds
• Plant out spring cabbage and winter salads
• Plant garlic cloves for next year
• Take strawberry runners for new plants
• Prune blackberries after fruiting
• Clear finished crops and compost debris

Greenhouse

Start reducing watering as growth slows. Bring tender plants under cover.

September Greenhouse Tasks

• Bring tender plants indoors before frost
• Pot up cuttings taken over summer
• Sow winter salads for greenhouse growing
• Reduce watering as growth slows
• Ventilate on warm days
• Clear out tomato and cucumber plants as they finish
• Clean greenhouse glass for maximum winter light
• Check for and repair any damage
• Install heater if overwintering tender plants
• Force prepared hyacinths for Christmas

House Plants

Bring outdoor houseplants inside as temperatures drop. Reduce watering and feeding.

September House Plant Tasks

• Bring houseplants back indoors before heating goes on
• Check for pests before bringing plants inside
• Reduce watering as growth slows
• Stop feeding most plants until spring
• Move plants to brighter positions
• Repot any pot-bound plants

Garden Maintenance

September is ideal for lawn care and general tidying before winter.

September Maintenance Tasks

• Scarify and aerate lawns
• Overseed bare patches in lawns
• Apply autumn lawn feed
• Clear leaves from lawns and paths
• Net ponds to catch falling leaves
• Clean and store garden furniture
• Check and repair fences before winter storms
• Top up gravel paths and drives