Garden Tasks for August in Acadiana: By Dan Weintritt and friends

Adapted from Month-by-Month Gardening in Louisiana by Dan Gill

Now is the peak of summer. Things will begin to get drier, as "heat showers"

drifting in from the Gulf cease. Rain for the next 10-12 weeks may only come

from hurricanes and tropical storms. Continue to monitor watering needs.

Plants in pots that are badly struggling can be cut back or moved to full shade

for the short term. If you are not able to up-size plants into larger pots,

consider lifting the plant, and root-pruning as well as cutting back foliage.

Cutting off an inch of girdled roots at the bottom of a pot can allow you to add

fresh soil, which will hold moisture throughout the day.

August is a month mostly for selective pruning and pulling. Plants that are

being rambunctious might be crowding out newer or less aggressive plants

nearby. Those that spread by runners, e. g., stolons and rhizomes, can be

contained by root barriers, going at least 8-12" into the ground. Make a plan to

lift and contain these plants in fall or winter. A 3 to 30 gallon grower's pot with

the bottom half cut off is oftentimes a free or cheap solution to corral an

unwieldy native. Herbaceous plants can be freely trimmed to size without

damaging them. Avoid trimming down fall-bloomers this late in the year; you

might not get flowers if trimmed this late, although trimming side growth to

prevent crowding is fine.

Be sure to have a water source out for wildlife. Insects, like bees, like a

shallow tray filled with gravel, where they can perch on a pebble and sip water

from between the stones. Birdbaths may need to be re-filled every day or

every couple of days. Even if they are not dry, the water should be dumped

and refreshed to get rid of mosquito larvae. If you have a water feature like a

pond, consider adding fish to eat mosquito larvae. Ponds should be at least

two feet deep and have some plant cover to keep the water cool enough to

support life.

Louisiana Irises, unlike most plants, go virtually dormant in late summer, and

it is an ideal time to divide established clumps. Irises have rhizomes, which

are large, fleshy, underground stems; and irises bloom best on new growth.

Old clumps of irises have nowhere else to spread, and therefore cannot put

out new growth. Reinvigorate these plants by dividing the old iris clumps. Lift

as much of the rhizomes from the soil as you can; rinse any extra dirt away

with a hose, if necessary. Break away 6-12" pieces of rhizome, which have

fresh leaves at the tips. These are the bits of new growth that will flower best.

The large, woody, old center of the rhizomes can be discarded or moved to a

new area. Opening up space in the soil will allow for renewed vigor for the

next few years. This can be done every 3-10 years, depending on need.

Light deadheading of repeat-bloomers should be done now, if you haven't

already. Gaura, Hibiscus, Rudbeckia and other daisy-relatives, Mountain Mint,

Salvias, and Mistflower will catch a second wind in fall if you selectively

remove some of the spent blooms and top-growth now. Plants that are doing

badly may be showing signs of new growth at the base. Trim them back to this

new growth; the plant is aborting the stems and foliage it cannot support in the

heat and is trying to give itself a fresh start. You can help it along by reducing

the liability of moisture-shedding tissue above the ground.

As things get drier, the pressure of new weeds sprouting from seed should

slow down. It will be difficult to hand-pull, if the ground is hard and dry. I

personally like to heavily water an area that needs weeding the day before

tackling this task. This softens the soil and makes it easier to pull the entire

root of weeds.

Continue to make plans for garden sites that need improvement, such as

weedy areas, or areas lacking bloom or interest. Transplanting and

propagating time is not far away. Look at what you have that you can multiply,

by division, cuttings, or seed.

Look for announcements of fall plant sales. Bulbs and seeds can be

procured for fall planting. Begin cold stratification of seeds in the fridge for 6-

12 weeks for plants that appreciate it. Continue to check seedpods for just-

papery, dried husks that can be collected now for spring sowing.