Frequently Asked Questions

It can be difficult identifying what is wrong with your plant and knowing what to do about it.  These are some of the questions we get asked on a regular basis. After reading this, if you still don’t have an answer, let us help!  We have a very well trained staff that can help answer your questions.  Put a sample in a sealed bag or container to bring to the Info Desk here at the Natural Gardener, and we will be happy to diagnose it for you free of charge.

Why does my lawn have yellow, dying patches in it?

This can be caused by Take All Root Rot (TARR) which has emerged in the past decade as a significant, often fatal, disease of turfgrass in Texas.  St. Augustine grass is especially susceptible, although Zoysia and Bermuda have been victims too.  It is a fungus with symptoms appearing mostly in the summer, though the disease actually spreads throughout the lawn in the cooler months of fall and spring.  The symptoms show up first as yellow uneven patches in an otherwise green lawn.  The ultimate result can be that the lawn dies in patches between one and ten feet in diameter.  The roots will be shortened, discolored, and eventually blackened and shriveled.  To properly diagnose TARR, a sample of the green lawn (sod) about a foot square, taken from the edge of a “sick” spot, may be brought into the Natural Gardener, where we will look under magnification for the mycelial strands of the fungus.  [TARR]

Why does my lawn have brown circular spots?

This can be caused by brown patch, which is a fungal disease that affects mostly St. Augustine grass.  The good news is that it is usually not fatal.  The bad news is that it looks ugly.  The symptoms are brown, fairly distinct, circular spots in the lawn occurring during cool, moist conditions of the autumn and early spring.  The St. Augustine runners (stolons) are healthy & green, but the leaves turn brown and rot.  Often, brown patch shows up in the same area each year. During the hot season, the lawn usually recovers.  If most of these symptoms are present, then your lawn most likely has brown patch.  Starting an organic lawn care program is the first and best step towards a healthy, disease-resistant lawn. [Brown Patch]

The leaves on my plants look speckled, what’s causing this?

This symptom can potentially be found on any plant in the landscape and it’s caused by spider mites.  These almost microscopic mites feed on the juices from the leaves.  The leaves will start to discolor appearing more speckled yellow, with almost the look of being sprinkled with salt and pepper.  When the infestation becomes severe, very thin webbing on the leaves and growing tips can be found. 

There are lots of small green/black/orange bugs on my plants – what are they?

Aphids are small 1/8” soft bodied insects that can be many different colors.  They cluster on growing tips and under surfaces of leaves. Large numbers can cause deformed growth, discoloration, and an overall lack of vigor. They secrete a sticky sap or “honeydew” that is deposited on the lower leaves quickly growing over with sooty mold.  The mold is only on the surface of the leaf not hurting it, just blocking the light.  These leaves can be wiped to clean them off.  If any new honeydew is discovered then there is continuing aphid activity.

I found some white grubs when I was digging my border, how do I get rid of them?

 These are usually not a problem in central Texas.  Just finding a few grubs is nothing to worry about.  Discovering more than 10 per square foot, however, could be problematic.  Having predators such as skunks, armadillos, and raccoons come and dig up the lawn looking for them can also be a problem. Use Beneficial Nematodes to get them under control.

What are those big bugs with strange looking legs that are crawling on my plants?

These could be Leaf-Footed Bugs – these insects are the scourge of the tomato grower!  They are large with a body of up to 2” long.  Leaf-footed bugs get their name from the wide flatten leaf like paddles on their back legs.  With a powerful proboscis they pierce the skin of the fruit feeding on the juices within.  The immature insects have red-orange body with black legs.  Nymphs are only 1/8” – 1/2″ long and cluster together on the fruit feeding in the same way as the adults.

Why did my squash plant suddenly die?

This can be caused by the Squash Vine Borer –  this daytime-flying, orange, grey, and black moth lays eggs on the plant, usually on the vine or leaf stem, that hatch into larvae that burrow into the stem where they hide and feed, eating the stem from the inside out. Once they eat through enough tissue the plant cannot get enough water to the leaves and it wilts.  Squash vine borer can be infuriating as many people are unaware they are even present until you walk out one day and see your plant completely and irreversibly wilted.   


Why is my tomato plant not setting fruit?

Most large fruited varieties do not set when temperatures are greater than 90 F; however, most of the cherry style and a hand full of other heat tolerant varieties will set throughout the summer.  It’s a great idea to include at least one heat tolerant variety so you will have constant production through the summer.

Why do my tomatoes have a large black spot on the bottom?

This is a condition known as Blossom-End Rot and it is not caused by a disease or an insect. This dry, brown/black lesion on the bottom of the fruit is a calcium deficiency triggered by uneven watering – too much or too little, planting in cool soil, or excessive nitrogen fertilizer. Future Blossom-End Rot can be prevented by watering regularly and mulching. The application of a calcium source such as gypsum or crab shell at the beginning of the season can help prevent blossom end rot before it starts.  Then just focus on the watering!

Why are my tomatoes splitting and cracking?

This can be avoided by keeping the soil deeply and evenly moist throughout the growing season, minimizing drought and/or overwatering stress.

My tomato plants look like they have a fungus, what could it be?

Numerous species of fungi infect tomato plants, such as Early Blight, Late Blight, Septoria leaf spot, as well as Verticillium and Fusarium wilt. They cause spotting, yellowing, leaf dieback, and vascular wilt.

I found a huge caterpillar on my tomato plant, what is it?

This could be the Tomato Hornworm which is the very large caterpillar of the Five-spotted Hawk Moth.  The tomato hornworm is by far the most dramatic of the insects in how quickly they eat the plant, causing large sections to disappear overnight. This cool pollinator comes out in the evening and resembles a hummingbird as it hovers to visit flowers in the garden.  The caterpillar can reach 3.5” in length and has a yellowish horn on its rear-end.  

How do I get rid of weeds?

See our page on Weed Control for details of various methods you can use.

What should I use to prevent weeds in my lawn?

Corn Gluten is a natural, organic, pre-emergent herbicide to help control both annual and perennial lawn and garden weeds. Those who use corn gluten properly as part of an organic maintenance program find their lawn and landscape healthier and more weed-free year after year. Under the right conditions, each application of corn gluten prevents a majority of the weed seeds from sprouting.  Timing is the most important factor in the effectiveness of corn gluten, as with any pre-emergent herbicide. The corn gluten must be present on the soil before the weed seeds sprout (germinate) in order to be effective. There are two different times of year when we can control most weeds in our area: late winter and late summer/early fall. Since weed seeds can germinate anytime of the year, in some serious weed situations it would be beneficial to reapply corn gluten every 6 weeks during the growing season.  Corn gluten will keep all seeds from germinating, including any you may put out yourself, so don’t use it where you want seeds to grow!

How should I water my landscape?

 Watering only 1 time a week is the goal, but twice a week is sometimes necessary.  Deep thorough soaking by running sprinklers for 30 min to 1 hr will supply an adequate amount of water. Ideally irrigation should avoid contact with foliage and be run first thing before dawn, as these practices decrease the chance of fungal disease.  Soaker hoses or drip irrigation is preferred for watering landscape plantings. Allow the soil to dry out to the consistency of a well wrung out sponge: cool to the touch but not soggy.  Water if it seems dryer than that.  The key to proper watering is physically checking the soil (digging into the soil some three or more inches) regularly to establish the proper timing and amount of water needed.

How much should I water my lawn?

 Water 1-2 times applying a total of 1-11/2” a week.  To check the amount of water your irrigation system emits, use tuna cans (the ones that are approx. 1” deep).  Place the cans in your yard where the sprinklers run just before your system operates, then check the contents afterward. If the cans are full, you have the right setting, if they’re not you will need to adjust your watering schedule.

How often should I water my trees?

 Trees have different watering requirements to a lawn, therefore they will need to be watered in different ways and with different amounts of water.  Water on your usual schedule (hose, soaker hose, drip or sprinklers). If you haven’t been watering, start with an hour in each “zone” or area of coverage under the tree’s canopy.  The following day, dig down about 5 inches deep with a garden trowel. Feel the soil at the bottom of the hole. The soil should be moist down to at least 5 – 8 inches.  The soil should feel like the surface of a sponge that’s been thoroughly wrung out: not too wet or muddy. If it’s sopping wet, that’s too much so cut back on your next watering day. If the soil isn’t moist at the bottom, add more time on your next watering day. Keep adjusting your watering time until you’re consistently getting the soil moist down to about 5 – 8 inches deep.  Allow to dry (not bone dry) between watering: for trees this could be anywhere from 2-3 times a week for newly planted trees, to once every 2 months depending on the age of the tree, time of year, and the amount of rain you have received.  The key to proper watering is physically checking the soil regularly, a few inches down, to establish the proper timing and amount of water needed.

How often should I water my pots?

 Ideally watering should be done only every few days.  You can water every day in a pot but it must be monitored closely to avoid overwatering.  Thoroughly saturate the soil making a pass with the hose multiple times to ensure even absorption.  Just because a pot has a hole in the bottom doesn’t mean your pot has good drainage.  The media or potting soil plays a vital role. Some potting soils hold more water than others.  Starting off with the right potting soil will make a world of difference.  Allow to dry out to the consistency of a well wrung out sponge: cool to the touch but not soggy.  Water if it seems dryer than a well wrung out sponge.  The key to proper watering is physically checking the soil regularly, a few inches down, to establish the proper timing and amount of water needed. 

My peaches have worms in them, what are they?

 The major fruit-attacking insect pest of peaches and other stone fruit in our region is the Plum Curculio. The juvenile or “worm” stage is a slightly curved, yellowish-white, legless, brown headed grub which is about 3/8″ long when fully grown. The adult stage is a small brownish-black snout beetle about 1/4″ long, mottled with lighter gray or brown markings. For advice on how to deal with this pest see the next question.

When should I spray my peach trees to prevent pests?

1. At leaf drop in the fall: Spray Sulfur or a Biological Fungicide to help prevent diseases.
2. During winter dormancy: Spray Neem oil, Organocide or another organic oil once a week for 2–3 wks.
3. At bud swell in late winter/early spring: Spray a fungicide as listed in #1 above.
4. Late winter is the time to control the Plum Curculio, which causes “the worm” in the fruit of plums, peaches, and sometimes apples. At Petal-Fall (5 days after bloom), and again at Shuck Split (14 days after bloom), spray an organic insecticide such as Kaolin Clay or Take Down Garden Spray. Petal-Fall is when 80% – 100% of the flower petals have fallen. Shuck split happens after the fruit has just barely formed and has just expanded enough to split its papery covering (the “shuck”). Repeat in 10 – 14 days for a total of 3 sprays.