Get excited - spring has officially arrived! It’s a busy month in the garden, but one of the very best, so celebrate by getting your hands dirty. In September, the veggie patch is begging to be filled with beans, carrots, celery and cucumbers; there are gorgeous marigolds, chrysanthemums and salvias to plant; and once you're done, it's time to protect all those delicate new vegetable and flower seedlings with animal-friendly snail pellets - always applied in accordance with package directions, of course!

Skip to what to plant in the garden in September

Skip to which plants need feeding in September

Skip to which plants to prune in September

Skip to garden pests, diseases and weeds to look out for in September

Skip to September's general lawn and garden care tasks

Skip to your September garden centre shopping list


What's flowering in Sydney gardens in September?

What to plant in Sydney gardens in September

Which plants to feed in September

  • As your garden is waking up from its winter dormancy (much like a 3-month nap), it'll be hungry - so fertilise everything from lawns to trees! Click here to find the best fertiliser type for your garden.
  • Fertilise camellias, daphne and azaleas once they’ve finished flowering. Kahoona is a popular choice for these acid-loving blooms.
  • Keep citrus well-watered and feed with a complete citrus food.
  • A soluble plant food such as Thrive Flower & Fruit Soluble Fertiliser will keep spring-flowering annuals blooming longer.
  • Don't forget your indoor plants - their needs change in spring, too! Start watering more frequently in September, and also fertilise fortnightly, right through to about March, with a specialist indoor plant formula.
  • Top up mulch. Composted pine bark is great, as are lucerne hay, pea straw and sugar cane. Woodchip mulches are particularly good for native gardens. Mulching your garden beds has the bonus effects of both stopping weeds finding their way through, and keeping your soil cool and moist! Click here to shop our wide range of bagged mulches.

Which plants to prune in September

  • Spotted some sad-looking leaves on your favourite indoor plant baby? Now's the time to tidy them up. Not only will your plant look much better, it'll help to encourage new growth. Double win!
  • Prune hibiscus, camellia, plumbago and poinsettia.
  • Native shrubs such as bottlebrush should be trimmed after flowering to encourage bushy growth. In the same vein, now's also the time to trim hedges, encouraging the kind of lush new growth that will keep nosy neighbours at bay.
  • Prune flowering peach after flowering. Do not prune edible peach trees this month.
  • Ornamental grasses looking a little on the sad side? Don’t be afraid to cut back to ground level. Conditions are perfect for them to reshoot and grow back better than ever.

Garden pests, weeds and diseases to look out for in September

  • Gently wipe over the foliage of all your indoor plants to help keep them clean - and check thoroughly for pests and diseases as you go. If you find mealy bugs, wipe them off with a cloth or use a horticultural soap such as Nature's Way Natrasoap Pest Spray to control them.
  • Protect vegetable and flower seedlings with snail pellets, like Multiguard Slug & Snail Killer (use as per product instructions).
  • Keep a close watch for aphids on new growth and spray with pyrethrum when necessary, particularly roses.
  • Azaleas and rhododendrons are best sprayed regularly to protect flowers from petal blight. Mancozeb Plus is the product to use.
  • Caterpillars are on the hunt. Keep them away with Nature's Way Caterpillar Killer Dipel or Success Ultra.
  • Spray viburnum tinus with Mavrik if two-spotted mites attack. They appear as red specks on the backs of leaves and cause silvering of foliage.
  • When they come into leaf, check grapevines for vine moth caterpillars and spray with Nature's Way Caterpillar Killer Dipel if affected.
  • Protect citrus against louse by treating with Lime Sulphur, and for leaf scale, spray with White Oil.

September's general garden and lawn care tasks

  • After its winter snooze, your lawn is springing to life - which means it’s hungry. Unfortunately, broadleaf weeds are also taking advantage of the perfect growth conditions. Help your lawn get off to a good start, strengthen its roots and beat weeds with a weed-and-feed combo, such as Yates Buffalo Pro Weed ‘n’ Feed Hose On, which is safe on grass but effective on all broadleaf weeds. If you'd rather a product that's solely focused on feeding, try a lawn builder, such as Scotts Lawn Builder All Purpose Slow Release Lawn Fertiliser, which will help strengthen roots, promote growth and thicken your lawn. A general application of top dress can also be useful at this time.
  • If your lawn is looking patchy, sow some lawn seed and fill in any dips and holes with top dress. For a quicker result, you can also use rolls of turf, cut to size in order to fill patchy areas. For more spring lawn care advice, click here.
  • As the weather warms up, be kind to our pollinating friends - they do us a very important favour, after all! Provide a bird bath or shallow water dish for birds, bees and other pollinators to drink from. Be sure to pop in a few rocks or sticks to ensure that small insects have a safe escape route.
  • Feed camellias with cow manure, or with azalea and camellia plant food such as Kahoona.
  • Keep gardenias well-watered and fed with complete fertiliser so you get the best summer flowering results. Again, Kahoona works really well here, or try a gardenia-specific formula such as Harry's Gardenia Food.
  • Prepare vegetable gardens by forking cow manure through the garden, then giving a thorough water before planting. Add blood and bone and sweeten the soil with garden lime.
  • Water gardens regularly as spring-flowering plants tend to get very thirsty when in flower.

Your September garden centre shopping list