Bagworms are one of the easiest insects to detect, but can also do great damage before they are noticed. They arrive usually in June as the eggs hatch and begin their feeding frenzy. It is at this stage that they are most easily controlled. They love the arborvitae family of plants, but can feed on anything with a luscious leaf on it. Plants such as maple, boxelder, willow, black locust, poplar, oak, apple, cherry, juniper and persimmon can all become victims of the bagworm.
Begin watching for bagworms in June. After hatching they will build their ‘bag’ around themselves as they are getting their first feeding. Their ‘bag’ grows with them as they eat themselves into adulthood. This is usually a couple of weeks later that the ‘bag’ releases an adult worm. The adult worms don’t usually last very long. The male will fly away from his bag to mate with the female. He will die shortly after mating. The female usually stays with her bag and uses it to lay her 500-1000 eggs. She will die about 5 days later. If mating is done early enough in the season, this cycle will happen a second time in the same year, but typically, these eggs will stay in the cocoon until next June.
The best treatment for the bagworms is using an insect spray that includes permethrin. You will want to apply weekly or at least every two weeks when you have a good infestation. There is only one organic chemical treatment that can be used very early in the larvae cycle. Bacillus thuringensis (Bt) can be used right at the egg hatching time to help control. Otherwise hand pulling or power washing off the ‘bags’ off the plant is the only organic control for bagworms.
Catching them early, being persistent with the control, and loving on your plants is very important to control bagworms.
What do I need to know about using manure in my garden?
Manure is relatively high in nitrogen content. This makes manure valuable for composting but can be problematic if fresh.The most important thing to know is that fresh manure and vegetable gardens do not mix, in fact it could be deadly. Amending soil with aged, well-composted manure is acceptable practice. By well-composed manure we mean that the compost has been heated to 130 – 140 degrees for 5 days or more than cured for a period of 2 – 4 months. This thorough processing in needed to allow beneficial microbes to outcompete disease pathogens.
One additional consideration about manure is that it is typically high in salt and some plants do not tolerate salt (e.g., begonia, carrots, green beans, onion, raspberry, among others). Salts naturally accumulate in areas of limited rainfall since the leaching effect provided by rainfall is not available. Adding a fertilizer high in salt can exacerbate the problem.
Even if you plan to use manure for plantings other than vegetables, care must be taken. Fresh manure can damage plants it may even kill seedlings. If you choose to use un-composted manure incorporate it into the soil in the fall to give it time to age before planting.
Research is finding that animal manure can contain herbicides that the animal ingested. These herbicides can have a negative effect on garden plants. Since it is very difficult to determine if manure is contaminated, it is suggested that manure be well-composted before use and that animal manures not be used to make compost tea.
It’s mid-July and I have very few tomatoes, what’s wrong?
There could be a number of reasons. Let’s start with refining the problem.
If you have a lush plant with lots of leaves and no flowers you may have too much nitrogen in the soil. You could neutralize this by adding bone meal or colloidal phosphate to the soil. If you are adding nitrogen to your tomato plants in the future wait to apply the fertilizer until after the fruit has set.
If your plants are forming flowers but they are dropping off the likely problem here in the southwest is the heat. Each year it seems that we go from a hard freeze to temperatures in the 90s in a few short weeks. The effect of high temperatures on tomato plants is somewhat dependent upon variety. Many varieties drop blossoms when the daytime temperatures exceed 92 degrees, others 95 degrees. Some varieties are more effected by high nighttime temperatures (above 72 degrees) than daytime temperatures. In general, heirloom varieties are fussier about temperatures than hybrids.
Problem with tomato plants forming flowers but no fruit seems to affect those varieties with larger tomatoes. Small varieties, such as cherry tomatoes, do not seem to experience the same problems with heat.
If your problem is lots of green tomatoes that are not ripening, the problem is likely prolonged heat. Lots of us slow down when the days are long and hot and the same seems to be true for our tomato plants.
The use of shade cloth can be helpful to give the plants a bit of a break from the hot desert sun that we experience.
What do I do about those horrible green caterpillars that are eating my chiles and tomatoes?
Those hungry pests are tomato hornworms and they can defoliate a plant quickly. The only way to protect your plants, once you know they are around your garden, is to go on a search and destroy mission. The telltale sign of a hornworm is that it will leave tiny black seeds (it’s poop) on the leaves below the hornworm’s location (which is most likely on the underside of a leave making them very hard to see). Pull these guys off by hand. If you have chickens, give the hornworms to them or leave them for your local birds or drop them in a bucket of soapy water but get those voracious pests away from your plants!
What can I do about squash bugs?
Manual removal is the most effective approach according to NMSU’s Entomologist Dr. Sutherland. Pesticides are of limited effectiveness. The best approach is manual inspection of the underside of leaves looking for and squashing those reddish brown eggs before they hatch and begin to destroy your plants. If a plant is severely infected with squash bugs you may have to remove it.
Last year I grew the most wonderful chile so I saved seeds and grew it again this year – but the chiles don’t seem to be as good, what’s happening?
Chiles cross-pollinate very easily. This is a particular concern if you save seeds. If you are growing hot chiles and bell peppers together and save the chile seeds you might be in for a surprise and possible disappointment with the chiles grown from those seeds. The different chiles may take on the characteristics of any of the chiles grown around them due to cross-pollination. Avoiding the problem is pretty simple – use floating row cover when the chiles are in flower. If you have only one variety of chile you may not experience the problem (unless you have neighbors growing peppers). Selecting a couple of plants to save the seeds from and covering those during flowering is a straightforward way to keep the flavor you love for future growing seasons.
Stay informed and up to date on all the latest SEMG news. Read the latest issue of our Newsletter.
There are many Master Gardener projects that need your support. We appreciate all of your efforts!
Become a Master Gardener
Interested in joining our program? Register for the Intern Classes running from February 2021 to May 2021.