September in the Garden – 2023 Edition

Greetings, Lakeway gardeners! September is here, and while it may normally herald the beginning of our lovely fall season, our Central Texas “weather break” (when we flip our weather pattern and switch from hot to cool temps) may not actually happen until late this month or even later in October. Hello, El Niño, where are you?

Over the past month, due to our lack of significant rain, Travis County has sadly progressed from a state of extreme drought to a state of exceptional drought. And no, there is no drought level worse than exceptional. Just like in August, we continue to have a high pressure dome reside over Texas, causing those triple-digit temps and no sign of significant rain. All outdoor watering should be strategic at this point. Maybe it’s time to let your grass go blonde!

But let’s try to look on the bright side: we will eventually get through this drought. The shorter fall days will trigger seasonal blooms for asters and other perennials, and allow us to plant cool-season flowering plants like snapdragons, dianthus, alyssum, pansies, and nasturtium. These bloomers like cool growing conditions, so definitely don’t plant until later in the month. Plant sugar snap peas and snow peas during the (cooler?) last two weeks of September too. With a little care and attention (plus strategic hand watering), you can still have a beautiful and productive garden this September, even in the midst of a drought.

Gardening Tips and Events

Below we have many more helpful garden tips for your September gardening to-do list. You can also visit the Lakeway Garden Club for even more fall garden tips and tricks. Our Events Calendar showcases our upcoming LGC Member Mixer on 9/7 and many local or online classes and special events happening this fall. And as always, happy gardening!

LGC Member News

Mark your calendars for our upcoming LGC Member Mixer on Thursday, September 7th at 10:30am at the Lake Travis Community Library. This casual get together will include discussions about gardening during droughts, waterwise gardening, native plants and creating bountiful fall vegetable gardens. We’d love to display photos of our members’ gardens, so please RSVP and send in your garden pix which we will share during our meeting. If you would like to request a future garden topic or have a specific question, please let us know. And thanks in advance for your RSVP!

Also currently we are looking for a few talented LGC members who have experience speaking to community groups about plants and other garden topics. If you have experience and are interested in becoming a certified Lakeway Garden Club speaker volunteer, please let us know.

September Garden Tips

Flowers to Plant

Alyssum, Sweet (mid Sept), Aster, Flowering Balsam, Begonia, Celosia, Cleome, Coleus, Coreopsis, Cosmos, Dusty Miller, Gomphrena, Hamelia, Jacobinia, Larkspur (mid Sept), Mexican Heather, Pentas, Petunias, Saliva, Verbena

Seeds to Sow

Beans – pole, snap, lima (early Sept)
Beets
Carrots
Cucumber (early Sept)
Greens – cool season (late Sept)
Leeks (late Sept)
Onions – bunching, multiplying
Peas – English, snow, snap
Potato – Irish (early Sept)
Radishes
Squash – summer (early Sept)
Turnips

Things to Transplant

Artichokes
Broccoli
Brussels Sprouts
Cabbage
Cauliflower
Garlic (mid Sept)
Shallots (late Sept)

Things to Sow or Transplant

Asian Greens
Collards
Kale
Kohlrabi
Lettuce (mid Sept)
Mustard
Spinach (mid Sept)
Swiss Chard

September Garden To-Dos

Fall is (normally) a time for planting!

Fall (normally) is the best time of year to plant perennials, trees, shrubs, vines, or groundcovers here in Central Texas. However this year in our exceptional drought it is a little different. So plant with caution until we get some significant rain. If we do get some wet weather, then go forth and plant! Fall is the time to plant wildflower seeds (you have until Thanksgiving), and there’s also a small window in early September to plant and establish native grass seed.

Consider native groundcovers instead of turf

Horseherb or frog fruit are an excellent native groundcover in shady areas. Horseherb has delicate yellow flowers, while frog fruit can tolerate full sun and has white flowers. Both can be mowed. Another native shady option is pigeonberry, which has pink flowers and tiny red berries that attract wildlife.

Divide perennials

Transplant, trade, or give away your divisions of iris, cannas, liriope, amaryllis, daylilies, violets, wood ferns, and other herbaceous perennials. Perennials should be divided every few years to keep growth uniform and vigorous. If your larger plants are beginning to show bald spots in the center, or you notice your bulbs not blooming as much as they used to, that’s a good sign it’s time to divide your plants.

Start a compost pile

Start gathering fall leaves for the compost pile. Why compost? First, composting decreases waste, reducing the problems associated with landfills. It is estimated that 40% of what we throw away can be composted! Second, proper composting transforms these wastes into a free soil amendment that adds nutrients, enzymes, and beneficial soil microorganisms, and improves soil texture, permeability, water retention, nutrient retention, and aeration. Finally, backyard composting is fun, and teaches children and adults about the process of decomposition and the creation of soil.

Take care of fall and spring bloomers

Fertilize roses and fall blooming perennials like asters and chrysanthemums. Add perennials, herbs, and ornamental grasses later in the month, making sure to water by hand until fall rains come. Plant spring flowering bulbs. Replenish mulch if needed. Deadhead flowers to encourage a last flush of petals. Prune reblooming roses this month if you haven’t already. Cut them back no more than 1/3. Shear hedges this month. Protect plants from antler-rubbing deer this month.

Watch out for brown patch in the lawn

Watch for brown patch as temperatures cool. Fall is the prime season for this fungal disease which affects mostly St. Augustine grass. Symptoms appear as fairly circular areas of brown patches, which may expand outward and may green up again in the center. While this disease is rarely fatal, it does look ugly. Treat when daytime temperature drops below 85° F. Continue mowing and follow the irrigation schedule provided by your water utility district.

Water strategically

Keep watering trees deeply and slowly until fall rains return. Stick with drought irrigation guidelines provided by your water utility district for all other plants. Let your grass go blonde this season until it rains.

TLC for your vegetable patch

This summer’s heat and drought have left most vegetables highly stressed, which curtails their blooms and therefore any fruit. All harvests can be expected to be well under normal yields this fall until rains and cooler arrive. Expect growth to slow down a bit as the days grow shorter and milder too. Let your southern peas dry on the vine, then shell and store in a cool dry spot until ready to eat over the winter. Seed root crops in moist soil; thin to the proper spacing soon after they emerge. Plant cool-season flowering plants like snapdragons, dianthus, alyssum, pansies and nasturtium. These bloomers like cool growing conditions so don’t plant until later in the month. Plant sugar snap peas and snow peas during the last two weeks of September, in cooler weather. Many veggie gardeners find the fall season to be more productive than spring in our area, so check out the Veggie Planting Calendar to plan your fall veggie garden.

Pests love dry, heat stressed plants

Continue to monitor trees and plants for fall webworms. Give those spider mites one last blast of water. Watch for caterpillars on brassica plants, then remove them by hand or carefully dust plants with Bt.

Plant winter cover crops

Always be sure to mulch any bare spots of soil, or better yet, plant a cover crop. Cover crops assist in preventing weeds just as mulches do, but they also improve the soil as they grow. Covering bare soil with a living plant helps insulate the soil from temperature fluctuations and helps to crowd out potential weeds. Cover crops can be planted in bare areas around existing crops as well, such as in vegetable gardens and around fruit trees. If it is feasible to till in the cover crop, it becomes known as ‘green manure,’ adding organic matter as well as nutrients to the soil.

The cover crops to plant in fall are red clover, hairy vetch, Elbon rye, Austrian winter peas, or annual rye. Till these in next spring or anytime before they flower, except elbon rye, which should be tilled in before it reaches a foot tall, before it becomes too tough to till. For all cover crops, wait at least two weeks, and preferably three or four, after tilling before planting anything else. This gives the organic matter a chance to decompose. Watering the area will help in the decomposition process. If you are using the cover crop as a “living mulch” around vegetables, wait until the vegetables are established, about 6″-8″ tall, before sowing the cover crop.

Garden Tips courtesy of The Natural Gardener and Texas AgriLife Extension.