Herbs for the Fall Season

The recent rains have brought new life to my garden, and my plants have rebounded after the heat and dry weather of August and September.  Fall time in Texas always seems to bring a new burst of energy to our landscapes, and I really enjoy the burst of color before winter.

Fall is a great time to plant and enjoy herbs in your landscape.  Herbs add great color and texture, and they can also be used for cooking, adding scents to your home and garden, and attracting pollinators.  Herbs have a great role to play in the kitchen because they can pack a flavor punch to your dishes and allow you to reduce sodium or sugar.  Additionally, herbs have antioxidants with great health benefits.

Cilantro and parsley are cool season herbs that can be planted now by seed or by transplant, and they add a fresh taste to salads and other dishes.  I have several varieties of sage and thyme in my kitchen garden, and they add beautiful color.  Purple sage is one of my favorites; the combination of purple and silvery green leaves is so pretty. (more…)

Thinning and Dividing Irises

The month of September has rolled by quickly, and I am somewhat behind on my monthly garden task list.  September is a great time to divide and re-plant irises.  I have some beautiful white irises that need a little more room, and I will be moving some of them to a new spot in my yard.

Iris beds do well if you thin them every two or three years.  Irises are rhizomes, which means they have a stem that grows horizontally just under the surface of the soil.  This creeping, underground stem will sprout stems and leaves upward and roots downward.  Thinning helps to promote new growth and blooms.

If you need to divide your irises this year, select a sunny, well-drained area in your yard.  I have grown irises in part shade before, but they do like to have well-drained soil.  Too much water will cause the rhizomes to rot.  If your yard does not drain water well, consider planting your irises in a raised bed. (more…)

Crape Myrtle Bark Scale

Last week, I was out for a walk and came to a quick stop when I noticed a crape myrtle with black leaves and trunks.  At closer inspection, I found hundreds of scaly, white things all along the trunks and branches.  These scale insects are Crape Myrtle Bark Scale.

Late summer seems to be the time that damage from CMBS really stands out.  They have had all spring and summer to reproduce and feed on the host plants, and now the honeydew and sooty mold are evident from a distance.

CMBS is a small, white, sap-feeding insect that lives on the bark of crape myrtle trees.  The adult females look like tiny pieces of popcorn attached near pruning wounds or in the branch crotches.  They are usually 2mm in length.  If you squish the scale, it has bright pink insides.  CMBS does not kill the tree, but it can cause reduced flowering and the scale secretes a honeydew that causes sooty mold. (more…)

Hornworms

The weather has been kind to tomato plants this year.  The rain and mild temperatures this summer helped my tomato plants survive and continue producing through July and even into August.  I am enjoying the abundant tomato harvest, and so are my coworkers, neighbors, friends, and even random people on the street.

Last week, a lot of leaves were stripped off my tomato plants, and I knew the culprit before I spotted it.  The tobacco hornworm is a three to four-inch caterpillar in the moth family Sphingidae.  It is bright green with diagonal white stripes and a red horn on the end.  The tomato hornworm looks very similar but has a black horn.  Both can be found on vegetable plants in our area, and they feed on blossoms, leaves, and fruit on the plants.

Despite the damage they do to tomatoes, eggplant, peppers, and potatoes, the hornworm is one of my favorite caterpillars.  They are so fat and look menacing with a horn, but they are harmless to humans.  Hornworms overwinter as pupae in the soil, and the adult moths emerge in the summer.  The moth from a hornworm is a large sphinx moth that is grayish brown.  It has a wingspan of four to five inches and feeds on nectar of flowers. (more…)

Lingering Frost Damage

In the week after Winter Storm Uri, one of our state horticulture specialists commented that we would be answering freeze damage questions for the next year.  He was right!  We are nearly six months post-freeze, and I answer freeze related questions daily.

The top two concerns that I hear about are trees that only have shoots coming out on the trunk and main branches and trees that have big cracks on the trunk.  The Texas A&M Forest Service released a great article this week to help homeowners determine if a tree is worth saving.

The summer heat is the true test of which trees survived the freeze.  Many trees have leafed out this summer and look healthy.  Some have a thinner canopy, but we expect them to look even better next year.  Trees with at least 50% or more of their normal canopy are likely to survive and continue to improve.

I have seen a lot of trees this summer that are almost poodle-like in appearance.  They have a bushy growth of shoots and leaves on the trunk, but very few or no leaves in the canopy.  By this point in the summer, that is a cause for concern. (more…)

Battling Armyworms

Armyworms are on the move!  Usually, we do not notice these little brown and yellow striped caterpillars crawling through the lawn. The weather conditions this year with all the rain has made for a heavy infestation of armyworms in parts of the county.  These worms march army-like in a line and can eat a whole lawn before you know what hit you!

The armyworm moths fly and mate at night, and a female can lay up to 1,000 eggs in masses on host plants, the underside of leaves, or even structures like fences and light posts.  The newly hatched larvae lower themselves to the ground with a silken thread and start to feed on turfgrass.  In the early stages, the larvae do not eat much, and they will eat the green tissue from the leaf blade leaving a transparent “windowpane.” (more…)

Watering Potted Plants

Potted plants are a fun way to add some accent color and greenery in your home and landscape.  I particularly love to grow geraniums in pots, and I have a decent track record of keeping them alive through the winter months.  I also love to hang potted ferns on my front porch.

Sometimes with potted plants it can seem like there is a fine line between too much water and not enough water.  A general rule of thumb for healthy potted plants is to use pots that have drainage holes in the bottom.  Drainage holes allow excess water to run out, which helps to avoid drowning the roots or root diseases.  Let the soil dry out between watering, and water again when the top inch of soil feels dry.  To ensure adequate watering, provide enough water until it starts to drain out of the pot.

Now for the interesting part! When many potting soils dry out, they can become hydrophobic.  Hydrophobic soils repel water and can be difficult to rewet.  Interestingly, many potting soils contain peat moss because it holds moisture, is lightweight, and decomposes slowly.  When peat moss dries out, it can be very difficult to rewet. (more…)

Stinging Caterpillars

One of the best parts of gardening is just taking time to observe the activity of nature.  The list of gardening tasks can be long: planting, weeding, watering, mowing, picking, pruning, and the list goes on.  But in between all the activity, I enjoy slowing down to observe all the life in my garden.

This week, when I slowed down to look, I noticed a big fluffy caterpillar making itself at home in my lamb’s ear.  It was tempting to run my finger along the fuzzy hairs of the caterpillar, but I have listened to my entomologist friends long enough to know that is not a smart move.  Some caterpillars can sting! (more…)

Summer Vegetables

We have been blessed with some good rain over the last couple of weeks, and gardens are blooming and producing great right now.  My biggest problem right now is making sure I beat the squirrels to my tomatoes.

June is a fun time to garden because of all the harvest coming in right now.  Tomatoes, blackberries, squash, green beans, and many more crops are ready right now.  June is also a good time to start thinking ahead to a few other crops like okra, sweet potatoes, and pumpkins.

Okra loves the hot weather of a Texas summer, so it’s not too late to get it planted. The biggest hurdle for growing okra in the summer is being willing to go out and pick it in the heat of July!  Some good varieties for Williamson County are Clemson Spineless, Hill Country Red, Burgundy, Emerald, and Stewart’s Zeebest.  Plant seed through the first week of July, and the days to harvest is 55-65 days. (more…)

Trees After the Freeze

In the early days after Winter Storm Uri, the message from horticulturists and arborists was “Be Patient.”  We wanted to see which plants were able to rebound from the freeze as they started the normal spring leaf out.  Fortunately, many of our trees, shrubs, and other ornamentals are doing great!

Nearly four months later, horticulturists and arborists are still preaching the same message about plants that don’t seem to be doing very well.  Trees are generating the most cause for concern, specifically some live oaks, Monterrey oaks, and Ash trees.

In February in Texas, trees begin the process of getting ready to do their spring leaf out.  They begin pulling nutrients up from the roots and pushing them into their branches and twigs.  The freeze was timed just right that all that energy the trees were using to prepare for spring leaf out was frozen and lost.  Now trees have to summon up more energy to try to create new buds and leaves.  That can take some time, and some trees might have enough other stressors such as disease, pests, or other environmental stressors that they just cannot recover.

Our inclination as caretakers is to help provide trees with water or nutrients or pest control to give the trees a fighting chance.  The Texas A&M Forest Service states it well, “Unfortunately, experts are saying there isn’t much you can do, and there is very little that you should do.”

Trees do not need extra fertilizer, which would promote growth.  That seems counterintuitive, but trees need to focus all their energy on keeping a healthy defense system.  A spurt of new growth from fertilizer only redirects energy away from a defense system.  Preventative insecticide and fungicide treatments should only be done on a case-by-case basis.

One thing you might do is provide one or two supplemental waterings per month when it gets hot later in the summer.  Trees do not need the extra water right now, so wait until it gets hot and dry in July and August.

If your trees have some leaves, continue to be patient, and see how they do next spring.  If the tree is completely bare in July, you can probably count on it being dead.  The hardest thing to do is wait, but trees do pretty well in the wild without our help.

For more information about lawn and garden topics, contact Horticulture Extension Agent Kate Whitney at the Williamson County AgriLife Extension Office at 512-943-3300.