What to Do With Lavender in September – 7 Jobs to Help It Survive Winter and Bloom Better
Don't put your lavender to bed just yet – September is the perfect time to tidy, propagate and prepare these fragrant plants for the months ahead
Lavender may be past its summer peak, but September is no time to forget about it. A few simple jobs now can help plants stay healthy as temperatures fall, while also giving you the chance to create new lavender plants for next year.
For US gardeners, the timing will vary considerably by region. In northern states, fall can bring chilly nights and early frosts, while gardeners in the South may still be enjoying warm weather. Wherever you garden, September is a useful month to check your lavender's growing conditions and prepare it for the seasonal shift.
If you're hoping to grow lavender or try landscaping with lavender, September is a good time to assess your plants and plan ahead. I love the Southern Living® Phenomenal™ Lavender Plant and Sensational™ Lavender Plant from Trees.com, with Sensational™ being an especially lovely choice because it blooms in fall.
Exploring different lavender varieties can help you choose plants suited to your local conditions, with factors such as size, hardiness, and flowering time to consider.
1. Tidy Spent Flowers
If your lavender has finished flowering, September is a good time to deadhead lavender by removing spent flower stems and lightly tidying the plant. Focus on shaping the green, leafy growth rather than cutting deeply into the woody base. For the job, I like the Fiskars Bypass Pruning Shears from Amazon, which are well suited to trimming flower stems and light branches.
Avoid heavy pruning late in the season, particularly in colder climates. Cutting too hard can encourage tender new growth that may struggle when freezing temperatures arrive.
2. Cut Back on Watering
As the summer heat fades, your lavender will likely need less water. Knowing how to water lavender properly is especially important in areas where fall brings increased rainfall. Lavender is drought-tolerant once established and prefers dry, well-drained conditions. Let the soil dry between waterings, and avoid keeping the root zone consistently damp, which can contribute to root rot.
For container-grown lavender, I like the Fiskars Indoor and More Watering Can, available at Walmart. Its long, slim spout makes it easier to direct water right to the base of the plant without overwatering.
If you're growing lavender in a container, also check that excess water can drain freely through the bottom.
3. Check Your Soil and Drainage
Before fall rains arrive, check where your lavender is growing. These Mediterranean plants dislike sitting in wet soil, so drainage is particularly important as temperatures cool. If you have heavy clay soil, consider improving drainage with suitable amendments or growing lavender in a raised bed.
If you're growing lavender in pots, make sure containers have drainage holes and use a free-draining potting mix. The Hayes Terracotta Planters from Pottery Barn are a stylish option for outdoor use, while the Bloem Terra Plastic Planter from Target offers a more budget-friendly choice with drainage.
Rachel Bull, Head of Gardens at Homes & Gardens, says: 'Lavender is happiest when you work with its natural preferences rather than against them. In September, that means keeping the roots on the drier side and making sure excess moisture can escape easily.'
4. Skip the Fall Fertilizer
It can be tempting to fertilize lavender with a final feed in September, but established plants generally don't need it. Fertilizing now can encourage soft, leafy growth just as the plant should be slowing down for winter. If your soil is reasonably fertile and the plant is healthy, there's little reason to add extra nutrients.
If you do need a fertilizer for lavender, choose a gentle, slow-release option and use it sparingly. Jobe's Organics Granular Plant Fertilizer from Amazon is one option to consider for plants that genuinely need feeding, but it's best saved for the active growing season rather than applied in September.
5. Take Cuttings for Next Year
September can be a great time to propagate lavender from cuttings, particularly if you have a plant with a scent, color or growth habit you particularly love. Take healthy, non-flowering shoots and remove the lower leaves before placing the cuttings into a free-draining rooting medium. A rooting hormone such as Garden Safe TakeRoot Rooting Hormone can help encourage root development.
Keep cuttings lightly moist and protected while roots develop. This is an inexpensive way to produce new plants for borders, containers or pathways – and a useful gardening job to tackle before the season winds down.
6. Inspect for Pests and Disease
Give plants a close inspection as you complete your September garden cleanup. Look for discolored foliage, dying stems or signs of lavender pests, and check that the base of the plant isn't staying excessively wet. Good airflow and drainage are essential for lavender, particularly as cooler and wetter weather arrives.
If you spot aphids, spider mites, or other soft-bodied pests, an insecticidal soap can be a useful option when used according to the label. Bonide Captain Jack's Insecticidal Super Soap from The Home Depot is one option that can help control several common garden pests. Always test sprays on a small area first and avoid treating plants when pollinators are actively visiting.
Removing affected foliage and improving growing conditions can help prevent small problems from becoming bigger ones.
7. Prepare for Your First Frost
How much protection your lavender needs depends on the variety and where you live. If you're wondering how to winterize lavender, start by checking your plant's hardiness before temperatures fall. English lavender (Lavandula angustifolia) is generally more cold-hardy, while Spanish and French lavender varieties can be less tolerant of freezing conditions.
If you garden in a colder USDA hardiness zone, be ready to protect tender varieties as genuinely cold weather approaches. Container-grown lavender is particularly vulnerable because its roots have less insulation than plants growing in the ground. A frost cloth such as this Plant Cover from Amazon can provide temporary protection, while a layer of natural burlap, such as Burlapper Burlap Fabric from Amazon, can offer additional shelter for containers.
Don't rush to wrap or cover healthy lavender simply because September has arrived. Wait until genuinely cold weather is approaching and make sure any protection still allows good airflow.
I use these Fiskars Bypass Pruning Shears in my own garden for fall jobs like deadheading lavender and lightly pruning the plants before winter. The sharp stainless steel blades make clean, precise cuts, making it easy to tidy lavender without damaging healthy growth.
Give your lavender a little extra love with this easy-to-use fertilizer, designed to help keep those fragrant blooms coming and that silvery foliage looking its best. The balanced formula supports healthy growth without making feeding feel like a chore. Use it for lavender in pots, borders or garden beds – basically, wherever your purple beauties are putting on a show.
Before winter sets in, give your lavender one last weed-free tidy-up. This 13.3-inch long-handle weeding tool makes it easy to evict stubborn dandelions, crabgrass, chickweed and thistles without disturbing your lavender. It’s a simple job now that can leave your beds looking neat and give your plants less competition as they head into winter.
Lavender doesn’t need much fuss in fall. I’ve managed to keep mine going year after year by avoiding overwatering, skipping fertilizer and not pruning too hard. Instead, I focus on good drainage, a light tidy-up and winter protection when needed. A little care now can help lavender stay healthy through winter and bloom again next year.
