September Gardening Guide: Welcome Fall to Your Southern California Garden
While much of the country is winding down their gardens, Southern California is just getting started.
September marks the beginning of our favorite gardening season. Warm soil encourages strong root growth while cooler evenings reduce stress on plants, creating ideal growing conditions for everything from trees and shrubs to vegetables, flowers, and lawns.
Whether you're refreshing your front yard, planting a vegetable garden, or preparing for colorful fall blooms, September is the perfect month to dig in.
What’s Taking Root This Month
Your September priorities at a glance.
- Take advantage of warm soil and cooler evenings to establish trees, shrubs, perennials, and lawns before next summer.
- Transition edible gardens from summer crops to cool-season vegetables, herbs, and strawberries.
- Refresh beds, containers, and entryways with mums, fall annuals, pottery, pumpkins, and seasonal accents.
What You’ll Find in This September Garden Guide
Why Fall Is the Best Time to Plant
Many gardeners assume spring is planting season. In Southern California, fall often produces better results.
Plants installed in September and October spend months developing healthy root systems before next summer's heat arrives.
Benefits include:
- Faster root establishment
- Lower water requirements
- Less transplant stress
- Better spring blooms
- Healthier trees and shrubs
- Stronger lawns
Tip from Our Garden Experts
Every week you wait to plant in fall is one less week your plants have to establish roots before next summer. Planting now can mean less watering and healthier plants next year.
Start Your Fall Planting Project
Warm soil and cooler evenings make September an excellent time to add trees, shrubs, perennials, and edibles.
Find Your Local ArmstrongRefresh Your Landscape with Fall Color
As summer flowers begin to fade, September is the perfect time to refresh containers, entryways, and flower beds.
Plant favorites like:
- Chrysanthemums (mums)
- Pansies
- Violas
- Snapdragons
- Cyclamen
- Stock
- Alyssum
- Primrose
Combine colorful annuals with decorative pottery and pumpkins to instantly transform your front porch into a welcoming fall display.
Plant Perennials That Return Every Year
Perennials provide reliable color while supporting bees, butterflies, and hummingbirds.
Great September choices include:
- Salvia
- Rudbeckia
- Echinacea
- Coreopsis
- Gaura
- Lavender
- Lantana
- Yarrow
Many continue blooming well into fall while creating valuable habitat for pollinators.
September Is Vegetable Garden Season
One of the biggest gardening transitions happens in September. As summer vegetables slow down, cool-season crops begin their growing season.
Now is the ideal time to plant:
- Lettuce
- Kale
- Spinach
- Broccoli
- Cauliflower
- Cabbage
- Carrots
- Beets
- Radishes
- Kohlrabi
- Arugula
Fresh herbs such as rosemary, oregano, sage, and thyme also thrive during the cooler months.
Late September is also a great time to plant strawberries for months of delicious harvests.
Grow a Fresh Fall Harvest
Transition your edible garden with leafy greens, cool-season vegetables, herbs, and strawberries.
Shop Vegetables & HerbsPlant Trees, Shrubs & Edibles
September is one of the best months to invest in your landscape.
Consider planting:
- Olive trees
- Dwarf olives
- Westringia
- Japanese boxwood
- Texas ligustrum
- Berry bushes
- Citrus where available
- Flowering shrubs
Always plant with a quality planting mix and root starter fertilizer according to label directions to encourage healthy establishment.
It’s Bulb Planting Time
Spring begins in the fall. Plant flowering bulbs now for colorful blooms next spring.
Excellent choices include:
- Bearded iris
- Freesia
- Ranunculus
- Anemones
- Daffodils
- Tulips after chilling, when required
Bulbs are one of the easiest gardening projects with some of the biggest rewards.
Plan Ahead for Spring Color
Choose a combination of early-, mid-, and late-season bulbs for a longer bloom period. Plant in well-drained soil and follow package directions for planting depth and spacing.
Lawn Care for the Season Ahead
Your lawn is preparing for cooler weather.
September lawn care should include:
- Continue mowing regularly.
- Water deeply, but adjust as temperatures cool.
- Repair bare spots with seed.
- Aerate compacted lawns if needed.
- Begin preparing for fall feeding.
Tip from Our Garden Experts
September is one of the best times of year to establish a beautiful lawn. While overseeding is a great option for repairing thin areas, it's also an excellent month to install fresh sod. The cooler temperatures and warm soil help new sod root in quickly while reducing stress and water needs compared to the heat of summer.
Healthy lawns established now can look their best throughout fall.
Houseplants Need a Seasonal Reset
As temperatures begin changing, indoor plants also need a few adjustments.
September is a great time to:
- Reduce watering frequency as growth slows.
- Remove damaged foliage.
- Feed actively growing plants as appropriate.
- Repot rootbound plants.
- Refresh your home with colorful varieties like crotons, aglaonema, calathea, and rex begonias.
Create a Cozy Fall Entry
One of the easiest ways to celebrate the season is with your front porch.
Mix together:
- Mums
- Pumpkins
- Decorative pottery
- Lanterns
- Ornamental grasses
- Seasonal wreaths
Even a small front entry can become an inviting fall focal point.
Bring Your Fall Landscape Vision to Life
September is an ideal time to begin a landscape project so planting can take place during Southern California’s prime growing season.
Book a Landscape Design VisitSeptember Garden Checklist
- Plant trees, shrubs, and perennials.
- Refresh flower beds with fall annuals.
- Plant cool-season vegetables.
- Start strawberries and herbs.
- Plant spring-flowering bulbs.
- Feed roses and remove spent blooms.
- Divide overcrowded perennials.
- Adjust irrigation as temperatures cool.
- Refresh containers with mums and seasonal color.
- Schedule your landscape design consultation for fall planting.
Frequently Asked Questions
Answers to common September gardening questions about planting, vegetables, lawns, fall color, and landscape projects in Southern California.
Is September a good time to plant in Southern California?
Absolutely. September offers warm soil, cooler evenings, and excellent conditions for establishing trees, shrubs, perennials, vegetables, and lawns before winter.
What vegetables should I plant in September?
Lettuce, spinach, kale, broccoli, cauliflower, cabbage, carrots, beets, radishes, kohlrabi, arugula, and many herbs perform beautifully when planted this month.
Should I still water my lawn as much?
Continue watering deeply, but begin adjusting irrigation schedules as temperatures gradually cool. Watering early in the morning can help reduce evaporation.
Can I plant trees in September?
Yes. Fall is one of the best times to plant trees because warm soil promotes strong root growth before next summer's heat.
Why are mums so popular in September?
Chrysanthemums bloom as the seasons change, providing long-lasting color that pairs beautifully with pumpkins, ornamental grasses, pottery, and fall décor.
When should I start planning my landscape project?
September is one of the best times to schedule a landscape design consultation so planting can begin during Southern California's prime growing season.
Make the Most of Southern California’s Fall Planting Season
September brings some of the year’s best opportunities to plant, refresh, and prepare your garden for the seasons ahead. By establishing new plants now, transitioning your edible garden, updating seasonal color, and adjusting your care routine, you can create a healthier and more beautiful landscape for fall, winter, and next spring.
For recommendations tailored to your garden and local microclimate, visit your local Armstrong Garden Center and speak with one of our garden experts.