Do Your Plants have Problems?

Do Your Plants have Problems?

When you don’t know what’s ailing your plant, ask an expert.

 

Many gardeners get stumped when a favorite plant of theirs comes down with a strange “something”. Many of these gardeners know about UF/IFAS Extension and call their local horticulture and agriculture agents for assistance in figuring out what’s going on. However, even these experts are often stumped by what they see. Fortunately, the agents have another layer of experts to fall back on. In addition to the resources in Gainesville, we have the Plant Disease Diagnostic Clinic, located at the North Florida Research Center in Quincy. Plant pathologists here can help determine what fungus, bacteria, virus, or viroid may be the problem.

 

Plant pathologists are basically plant doctors. They use all sorts of sophisticated techniques to determine what is the cause of a particular plant problem, from growing out fungal spores to examining DNA. Not only do these plant doctors tell us what the ailment is, they also provide recommended cures, or control options. They are also doing research to prevent different diseases from taking hold in our area and reduce the impact on our local growers.

 

Plant pathologist at work!

 

At a recent workshop in Quincy, we learned that plant pathology researchers are working on a fungus that affects watermelons, virus and bacteria that can wipe out a farmer’s tomato crop, and a virus that could impact our local roses. Working as a team of scientists, they study these pathogens in the lab and conduct controlled field experiments to figure out which techniques are most effective. Some of this research is leading to different methods and/or products that can help growers and gardeners alike keep their fields and landscapes healthy.

 

So, if your plants have problems, please contact your local Extension Office. If they don’t know the answer, then the network of scientists, including plant pathologists, in the UF/IFAS Extension family can be called on for backup to provide you with the best possible answer.

Control Grasshoppers When They Are Young

Control Grasshoppers When They Are Young

Young nymphs of the eastern lubber grasshopper, Romalea microptera (Beauvois), clustered on a citrus reset (young citrus tree). Photograph by John Capinera, University of Florida.

Young nymphs of the eastern lubber grasshopper, Romalea microptera (Beauvois), clustered on a citrus reset (young citrus tree). Photograph by John Capinera, University of Florida.

The Eastern Lubber Grasshopper, also known colloquially as the “Georgia Thumper,” can be highly destructive to a variety of vegetable crops. This May many growers and vegetable gardeners have reported unusually high numbers of nymphs, the juvenile form of the grasshopper.

This observation is consistent with the usual increase of nymphs in vegetable gardens during the spring months. The old adage of “an ounce of prevention is worth a pound or cure” applies here. Now is the time to exert control over the nymphs before they mature. Adults do the greatest crop damage in July and August.

Additionally, adult females lay their eggs in the summer, with hatching the following April. Reducing the numbers this year will reduce the numbers in the following years.

The first step to control of the Eastern Lubber Grasshopper is prevention. They like to feed on weedy vegetation, so reducing weed cover in and around crops will reduce the incidence of Eastern Lubber damage. Short vegetation does not usually provide enough forage for grasshoppers, so mowing vegetation around fields is an excellent preventative strategy.

Although most home gardeners can control Eastern Lubber Grasshoppers by mechanical means (hand picking) this is usually not a feasible option for large gardens or small farm plantings. Fortunately, there are several products on the market for commercial producers to use.

Keep in mind, grasshoppers are much easier to control while they are in the young nymph stage, so early action is paramount when nymphs are observed. Several effective insecticides include carbaryl, bifenthrin, cyhalothrin, permethrin, and esfenvalerate. Look at the label to find these active ingredients, since they are sold under various brand names.

For more information about the Eastern Lubber Grasshopper or for specific crop recommendations, please visit this UF/IFAS publication on Grasshoppers and the UF/IFAS Featured Creatures Entomology Page.

 

What’s in Your Manure?

What’s in Your Manure?

Humans have used animal manures to fertilize food crops for thousands of years. Manures are an organic source of plant nutrients and are often a waste byproduct that must be properly managed when raising animals. Today, many farmers and backyard gardeners continue to use animal manures to provide nutrition to their crops. However, a recent experience at our local extension office brought to our attention the need to know what else, besides nutrients, is in the manure used.

A local backyard gardener brought in samples of tomato plants that had strange new growth. She had purchased the tomato plants, along with other vegetable plants, from a local nursery. When she repotted the tomato plants into larger pots, she added horse manure from her own horses to the soil mix. She then noticed this strange growth on the tomatoes, but not in the other vegetable plants that were repotted without adding horse manure. Herbicide damage was one of the first potential causes we suggested, since the new growth was twisted and distorted, a common symptom of plants that have been sprayed by herbicides. The gardener was sure she had not sprayed any herbicides near these plants, or in the pasture where she keeps her horses.

 

Herbicide damaged tomato plants. Photo by: Mark Tancig

Herbicide damaged tomato plants. Photo by: Mark Tancig

 

Photos of the tomato plants were shared with other NW District agents and an agriculture agent with livestock and hay producer experience had the probable answer – herbicide damage due to the horses being fed hay from a hayfield that was treated with a particular herbicide. Interestingly, this agent also had experience with these symptoms after their neighbor had similar issues using manure to fertilize the garden.

Herbicides with the active ingredients picloram or aminopyralid are able to cause this kind of unexpected damage to many gardeners’ crops. Herbicides containing these active ingredients are used in hayfields to control broadleaf weeds. These herbicides are especially effective at controlling hard to manage weeds such as thistle, nightshade, and nettle. They also provide long-lasting weed control. Unfortunately, the persistence of these ingredients extends into the hay, and also persists in the manure and urine of animals who eat hay from treated fields. These ingredients pass through the animal unchanged and remain active as an herbicide. Since many vegetable crops are broadleaf plants, the herbicide’s ingredients cause injury.

So what can a farmer or backyard gardener do to prevent this problem? When purchasing hay for livestock, ask the seller if they know whether the hayfield has been treated with herbicides that contain either picloram or aminopyralid. Most herbicides are known by their common names, rather than their chemical name. If they give you a common name or brand name, the active ingredient can be obtained by contacting your local extension office. If the seller can’t tell you, then, as a precaution, do not use the manure to fertilize broadleaf vegetable crops. The same question should be asked if purchasing hay for mulch as well. Composting the manure or hay does not break down the active ingredient, and may even concentrate it.

While we continue to use animal manures to fertilize our crops as our ancestors did, it’s important to remember that many of the tools and products we use today are much more advanced. These advanced products require that we stay informed of all precautions, use them responsibly, and, in this case, inform end users of any precautions. Remember to always read and follow the label and ask questions. And if a science-based answer is what you’re looking for, your local extension office is a good place to go!

 

Warning from herbicide label.

Warning from herbicide label.

 

Caterpillars in the Vegetable Garden

Caterpillars in the Vegetable Garden

In the last few weeks, more garden pests have arrived! It is a fact of life in northwest Florida that we will have a few things in our garden including heat, moisture (humidity and rainfall), and BUGS! With a cooler spring the arrival of some of the troublesome pests in the garden seemed to be delayed a few weeks. It was nice while it lasted but the insect pests are here to stay until frost in the fall or winter (at least we hope for a frost this year).

There are thousands of insects that you can see in your garden. It’s wise to identify them before making a decision to spray an insecticide or remove them by another method. Insect samples can be taken to your local county extension office for identification.

In this article we will just discuss one of the top insect pests in the vegetable garden, caterpillars, and what you can do about them.

Mature larva of the cabbage looper. Photograph by John L. Capinera, University of Florida.

Mature larva of the cabbage looper. Photograph by John L. Capinera, University of Florida.

Beet armyworms, fall armyworms, hornworms, cabbage loopers, southern armyworms, tomato fruitworms, and other caterpillars love to feed on tomato foliage and fruit. They will show up eventually on tomato plants in the garden, if not this year then in the future. These larvae are immature moths and cause a lot of damage if left unchecked. The homeowner can control them effectively with Organic Materials Review Institute (OMRI) approved pesticides. A bacterial biological insecticide called Bacillus thuringiensis, also referred to as B.t., can be very effective in controlling these caterpillar pests. B.t. is a stomach toxin to these pests and will cause them to quit eating and starve to death. The key to using B.t. effectively is to routinely apply it before the caterpillars hatch from their eggs as the smaller caterpillars are easiest to control. Larger caterpillars are more difficult to control.

For more information related to using OMRI pesticides:

Organic Vegetable Gardening in Florida

Insecticides for Organic Commercial & Backyard Vegetable Production

 

Don’t Think You Have a Green Thumb? Try Container Gardening!

Don’t Think You Have a Green Thumb? Try Container Gardening!

Banana pepper in container. Photo by Molly Jameson.

Banana pepper in container. Photo by Molly Jameson.

Interested in having a garden, but have limited space? Maybe you live in an apartment, have poor soil quality, or you just don’t have many areas that get enough sunlight. Maybe you’ve tried gardening, but given up, labeling yourself as one of those who “just doesn’t have a green thumb.” Well, I’m here to tell you, don’t give up! Try container gardening. Growing your own vegetables in containers is easy and can be a very rewarding experience. Container gardens also tend to have fewer weed, pest, and disease problems then regular in-ground gardens. Following just a few guidelines, you can have a bountiful harvest of fresh fruits, vegetables, and herbs right by your front (or back) door-step!

Grow vegetables easily in a large planter. Photo by Molly Jameson.

Grow vegetables easily in a large planter. Photo by Molly Jameson.

So, what are these guidelines, you ask? Well, you first want to choose the right container. This could be a large flowerpot, window box, planter, 5-gallon bucket, half-barrel, recycled material…the list can be endless. Just as long as your container is big enough and has proper drainage. Generally, the container should be at least 10 inches wide and 10 inches deep. The bigger the better, as it will give the roots more space to grow, and the soil will not dry out as fast. Tomatoes, for instance, do best in larger pots, preferably the size of a five-gallon bucket. For many herbs, you can get away with planting two or three different types in the same container. It is also important that your container has drainage holes, so water can escape and air can circulate. Use a one-fourth inch drill bit to create holes in the bottom or along the sides near the bottom of the container if it does not have holes.

Most of us know plants need both sunlight and soil. But just how much sunlight and what type of soil? If you are growing vegetables, it is best to have full sun – which means at least six hours of direct sunlight per day. An advantage of growing in containers is that you can easily place a container in an area of your yard or on a balcony that receives adequate sunlight, when it would be much more difficult to build a garden in these same areas.

Buy potting soil in bulk to cut down on costs. Photo by Molly Jameson.

Buy potting soil in bulk to cut down on costs. Photo by Molly Jameson.

So what about soil? When growing in containers, you want to make sure you get potting soil that is made for containers. These mixes will contain materials such as peat, perlite, and vermiculite for both good drainage and moisture-holding capacity, and materials such as compost and nutrient amendments that will keep your plants healthy. You can simply ask your nursery specialist for a mix formulated to grow vegetables in large outdoor containers. If you are growing a lot of vegetables, you can cut down on costs by making your own mix. Just make sure you have a good balance of the aforementioned materials, and mix in a slow-release vegetable fertilizer, following directions on the label.

Now that you have your container, your soil, and a sunny location, it is time to get the plants. Some plants are best bought as transplants or grown from seed started indoors. Vegetables such as broccoli, collards, kale, tomatoes, eggplant, peppers, and strawberries fall into this category. Other plants, such as root crops, arugula, lettuce, spinach, mustards, beans, peas, cucumbers, squash, okra, cilantro, and basil can be started from seed directly into containers.

For some vegetables, buy transplants from your local nursery. Photo by Molly Jameson.

For some vegetables, buy transplants from your local nursery. Photo by Molly Jameson.

Okay, so you have all the materials. Now what? If you are growing from transplants, first thoroughly moisten the potting mix and the plant’s soil. “Transplant shock” is reduced when there is proper moisture. Set plants at about the same level they were growing in their original pot. For tomatoes, remove lower leaves and plant deeper in the container. If you are growing from seed, simply plant the seeds according to their label. A good rule of thumb is to plant the seed to a depth of about two to three times the seed’s diameter. If you are worried about your seeds not germinating, go ahead and plant more seeds than you need. But remember to thin to appropriate spacing if they do, indeed, all come up. Spacing will be specific to the type of vegetable.

After planting, water gently but thoroughly. Monitor your container garden, making sure the potting mix does not dry out. You can reduce evaporation by mulching with leaf litter, straw, or a similar material. Plants that grow tall or produce vines, such as tomatoes and cucumbers, will need support. A wire cage or pole, inserted into the container at planting time, will support the plant as it grows.

Last step is to call over all your friends and family and show off your beautiful vegetable plants! They will surely be impressed by your “green thumb” and will be eager to learn your gardening secrets.

 

Start Planting the Spring Vegetable Garden

Start Planting the Spring Vegetable Garden

With weather warming up and daylight savings time right around the corner, we are in the midst of prime time for planting spring vegetable gardens. Gardeners routinely growing vegetable gardens should note that it is best to rotate plant families when planning a vegetable garden. See the table below to determine which families should be rotated.

* okra is not a member of the solanaceae, but may be included as part of the solanaceae rotation

* okra is not a member of the solanaceae, but may be included as part of the solanaceae rotation

SONY DSCVegetable gardens should be located on sites receiving at least 6 hours of sun per day, consisting of well-drained soil rich in organic matter. Since most Florida soils are low in organic matter, composted organic matter should be added before or at planting time. Uncomposted organic matter should be mixed into soil one month before planting. Vegetable garden pH should be between 5.8 and 6.3 to maximize absorption of nutrients. If it is lower, addition of agricultural grade lime or dolomite will be necessary. Obtain a soil test from your local extension office to determine if liming is needed.

Once soil test results are available, fertilizer amounts will be able to be determined. Many gardeners use commonly available fertilizers such as 10-10-10 or 8-8-8, with micro nutrients, following directions on the package to determine the amount to apply. The soil test will determine if phosphorous is needed, so follow those results when choosing a fertilizer. When fertilizing, broadcast the fertilizer over the garden area at pre-plant, then apply as needed throughout the season. This will likely consist of 2-3 light applications applied beyond the reach of the outer leaves.

Irrigation of vegetable gardens is best done with drip, so that fungal disease is not spread by getting leaves wet. An added benefit of drip irrigation is a reduction in the quantity of water needed. Gardens may also be top dressed by mulch or organic matter to aid in water conservation and soil temperature reduction.

In March, bush beans, pole beans, lima beans, cantaloupes, sweet corn, cucumbers, eggplant, okra, peppers southern peas, sweet potatoes, summer squash, and tomatoes may be planted. Some crops grow easier from transplants, while others grow better from direct seeding.

Tomatoes, peppers, eggplant and sweet potatoes are best established by transplanting. Cucumbers, cantaloupes, summer squash, beans, peas and okra are best established by direct seeding. Summer squash may be transplanted, but is more vigorous and productive when direct seeded.

Be sure to choose varieties adapted to North Florida by consulting the charts on pages 8, 9 and 10 of the Florida Vegetable Gardening Guide.

Happy Gardening!