What is a Master Gardener and How do I Become One?

Becoming a Master Gardener

Tom Ingram: Ask a Master Gardener

Sunday, August 05, 2018

Q: At the beginning of each of the classes we teach in elementary schools throughout Tulsa County, we typically ask the students a question: Who knows what a Master Gardener is?

A: We get all kinds of answers (as you might imagine) — “someone who is good at gardening” (we hope), “someone who likes insects” (most of the time) and “someone who likes plants” (always yes.)

Truth is, the question does not come with a simple answer because Master Gardeners do so many different things.

By definition, Master Gardeners are volunteer educators for the Oklahoma State University Extension service on a mission to provide research-based horticultural information to local home gardeners and the community. But, that mission can take many forms.

One of the ways we fulfill that mission is by staffing a horticultural Diagnostic Center at the OSU Extension office Monday through Friday. Between the hours of 9 a.m. and 4 p.m., you can find Master Gardeners on hand to answer your questions via phone, email or in person. Outside our Diagnostic Center, you will find our beautiful Master Gardener-maintained demonstration garden containing more than 200 annuals, perennials, shrubs and trees.

We also teach a variety of classes, such as our spring and fall Lunch and Learn series at the Tulsa Central Library, or our yearly Urban Gardener classes. Topics include plant biology, soil chemistry, growing fruits and vegetables, lawn care, tress and shrubs, flowers, container gardening, etc.

We mentioned the public schools. Master Gardeners teach a variety of science-based classes to elementary school students throughout Tulsa County. Last year, we taught these classes to approximately 16,500 students.

In addition, each year we also host an Insect Adventure for more than 1,000 third-graders, which helps these students gain a respect for the wonderful variety of insects we share this planet with and the many benefits they provide.

You may also have seen Master Gardeners at an Herb Festival or perhaps at our beautiful exhibit at the Home & Garden Show. Or, you may have visited one of our homes in the Master Gardener Garden Tour we host each spring.

Some Master Gardeners visit nursing homes to spend time with seniors while engaging in a little horticultural therapy to brighten their day. Others landscape yards for Habitat for Humanity homes so these new homeowners don’t just get a house but a beautifully landscaped home. And other Master Gardeners spend hours planting and maintaining beautiful flowers in planters in the Brookside and Blue Dome districts to help keep Tulsa beautiful.

So, now that you know what a Master Gardener does, do you want to come join us? At 10 a.m. Aug. 8 and 1 p.m. Aug. 15, you can attend a presentation at the OSU Extension (4116 E. 15th St.), where you can find out the requirements to become a Master Gardener and fill out an application. This enrollment only happens once a year, so if you have an interest, be sure to attend one of these presentations.

Garden tips

• Fertilization of warm-season grasses can continue if water is present for growth. Do not fertilize Bermuda or zoysia lawns after the end of August. Do not fertilize fescue lawns until it cools off in September.
• Mowing heights for cool-season turf grasses should be at 3 inches during hot, dry summer months. Gradually raise mowing height of Bermuda lawns from 1½ to 2 inches.
• Cucumbers may be bitter this time of year and vines quit producing. This is due to the heat. If you are able to get the vines through the summer, after it cools, they will be fertile again and the taste of the cucumbers will improve.

Azalea Problems and Proper Care

Azalea Care

Brian Jervis: Ask a Master Gardener

Sunday, July 22, 2018

Q: I have azalea bushes that are so beautiful in the spring but then develop problems over the summer. Should I just live with these issues or is there something I can do to help make them look better through the summer? Michelle T., Broken Arrow

A: Landscapes bursting with healthy plants give us splashes of color that change with the seasons, and azaleas are ideal centerpieces for flowering shrub beds, containers and even hedges.

However, the dream of such garden beauty sometimes comes into question when spots and holes appear in leaves, the foliage turns yellow or flower buds remain closed. While azaleas can withstand many of the insect and disease problems that plague other plants, there are still a few problems that can occur.

First of all, plant in the right location (east facing with good morning sun is the best), with good drainage and air circulation between plants to help prevent problems. However, when that is not sufficient, here are a few of the most common offenders:

Aphids: These may appear on the stems of any plant when the weather is humid and plants are too close together without enough air circulation. Treat aphids with a hard spray of water from the hose.

Lace bugs/spider mites: Azalea lace bugs make up about 90 percent of all azalea pest problems. They feed on leaves, creating speckled areas on the leaf surface. Spider mites cause white stippling on leaves first, but then the area turns a rust or gray color. Both can be treated with insecticidal soap, horticultural oils or a systemic insecticide that includes the ingredient imidacloprid. Use it as a soil drench once yearly after blooming to avoid harming bees.

Fungus-related issues: Leaf galls, rust, petal blight and leaf spot are caused by fungus. Petal blight appears as tiny white spots on flowers. Leaf spot manifests as brown blotches that grow in size. Treat with a fungicide.

Root rot/water mold: Azaleas may also be impacted by another fungus that causes root rot, sometimes called water mold. Azaleas that stand in water during warm weather are particularly susceptible. This occurs mostly when azaleas are planted as a foundation plant near a down spout. This fungus spreads fast, so watch for yellowing leaves and wilting plants.

Iron Chlorosis: Azaleas prefer acidic soils. If not planted in such, leaves will turn yellow. With this condition, a soil test is always in order, which can confirm the actual soil pH.

To assist in preventing these issues, azaleas should be mulched with several inches of pine bark, and some of the bark should be incorporated directly into the planting soil to help add oxygen and ensure thorough drainage.

Protect your valuable and beloved plants with regular attention, looking carefully for potential problems along stems and branches, as well as under leaves. And, when it comes to chemicals, more is never better. Small infections and infestations may go unnoticed, only to grow into larger issues later. Therefore, it is best to examine your azaleas every time you water.

For more information and assistance with azaleas, drop by the Tulsa County Extension Office or call the Master Gardener hotline at 918-746-3701 to speak with a Tulsa Master Gardener.

Garden tips

·        When watering your lawn, ornamentals or vegetables, always do so in the morning, if possible. If watered in the evening, plants will go into the night still moist. Most disease-causing organisms need moisture and, because they grow best at night, leaving leaves wet in the evening will promote many plant diseases.

·        Bulb onions are ready to harvest when the tops fall over. They should be removed and allowed to dry in a well-ventilated, shaded area. After the tops are completely dry, they may be stored in a cool, dry area.

·        Tomato production stops in the heat of the summer. Most tomato pollen becomes infertile and blossoms drop off when the night temperatures are above 70 degrees and daytime temperatures are above 92 degrees for a few days. Tall, spindly tomato plants with scarce fruit are usually due to either too much nitrogen fertilizer or too much shade. If this occurs, cut them back by ⅓. New growth and fertile blossoms will develop when it cools in the fall.

Squirrels and Other Pests in the Vegetable Garden

Squirrels and Other Pests in the Vegetable Garden

Allen Robinson: Ask a Master Gardener

Sunday, July 08, 2018

Q: Squirrels and other animals are eating my tomato plants. Help! What can I do? — Melissa R., Tulsa

A: Keeping animals out of tomato plants can be difficult and methods vary depending on the animal. For example, keeping deer out with a fence can be tricky because they can jump a fence shorter than about 9 feet. A barking dog is often the best deterrent for deer, and cats can be effective protectors against squirrels and other small animals. For some burrowing animals, a fence must be buried several feet deep to keep them from digging under it. And, for highly intelligent and adaptable raccoons, only a full cage may keep them out of tomato plants. Fake owls or snakes can help keep rabbits at bay.

With their acrobatic maneuvers and feisty chattering, squirrels often inspire smiles and laughter. But for gardeners who find beds dug up and tomatoes chewed, these bushy-tailed critters aren’t a source of anything except frustration and a fervent desire to figure out ways of keeping them out of the garden. They sometimes eat part of a tomato and leave the rest behind. Other times, they eat the entire fruit. Other favorite meals of squirrels include beans, squash, cucumbers and eggplants. And, occasionally, squirrels will unearth young potted plants in their quest to bury nuts.

Like other rodents, squirrels have long incisor teeth that never stop growing, so they tend to gnaw on all sorts of materials to keep those teeth on the short side. Various anti-squirrel techniques are recommended, depending on your preferred plan of action.

Here’s a listing, from harmless to harmful:

Clean up: The sight and smell of fallen fruit, nuts and seeds can lure squirrels to your yard for feeding. Clean up these items beneath trees and bird feeders. Make sure trash can lids fit securely to keep squirrels from discovering treats in the garbage.

Structure: Erect a fence. Wire fencing, such as hardware cloth, plastic bird netting or chicken wire, can keep squirrels out. Be sure to bury the wire deep so they can’t dig under it; keep the wires close together so they can’t squeeze through it.

Annoy them: Bother the squirrels by using motion lights or commercial devices that make high-frequency sounds. Surround the garden with unpleasant repellents, such as garlic, ground hot peppers or urine from predators such as wolves. Search online for products that contain capsaicin, the ingredient that gives hot peppers their heat.

Scare tactics: Having an outdoor dog or cat will drive squirrels away. Barn owl houses also scare squirrels away because owls are known to eat squirrels. Many have success simply with fake snakes.

Permanent solutions: If all else fails, consider commercial traps or poison. Place bait, such as peanut butter or sunflower seeds, in a live trap. When a squirrel is captured, release it far away from the garden. If you are not opposed to killing squirrels, you can also use poison bait traps, but be sure to follow the manufacturer’s instructions.

Garden tips

• For all your plants, ornamental or vegetable, mulching and correct watering are keys to surviving the heat of the summer. Mulch conserves water and reduces ground temperature.
• Fescue lawns need 2 inches of water per week to survive summer; Bermuda grass needs about half that amount. Watering less frequently and more deeply is much better than daily shallow watering.
• Brown patch disease of fescue lawns is appearing now, related to excessive rains, high heat and high humidity. Wet grass leaves promote the disease. Therefore, if you water in the mornings, allowing the leaves to dry during the day, there will be less likelihood of infections. Fungicides are available, but OSU feels the fungicides available to homeowners are not nearly as effective as those available to professional licensed applicators. None of these chemicals will cure existing infections; they only prevent new disease at best.

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Tomato Growing Challenges in Oklahoma

Tomato Growing Challenges

Brian Jervis: Ask a Master Gardener

Sunday, June 24, 2018

This time of year, we get a lot of questions about one of our favorite garden crops: tomatoes. We love our tomatoes, but there are a variety of challenges associated with growing them.

One of those challenges is Septoria leaf spot. Septoria leaf spot is a common fungal disease in Oklahoma. Starting at the bottom of your plant, you will notice leaves with yellow areas that become circular with grayish centers and dark borders. The spores from septoria can be quite aggressive, spreading upward throughout the plant.

When you see this, it’s time to begin a fungicidal spray program of copper fungicide on a 7- to 14-day schedule. This will not cure the infected leaves but will diminish its ability to spread. Infected leaves should be removed.

Also, to minimize exposure and spreading of fungal diseases, tomatoes should not be watered via an overhead sprinkler system, as the splashing water tends to provide a means through which the disease can migrate. Drip irrigation is preferable in most instances.

If you are having problems with fungal diseases, be sure you are rotating your crops. Planting the same crop in the same spot year after year tends to encourage these fungal diseases to develop. However, when rotating crops with tomatoes, do not put peppers, eggplants or potatoes in the same rotation as they all tend to be susceptible to many of the same diseases.

Another common challenge to growing tomatoes successfully is blossom-end rot. Symptoms manifest in an expanding, tan, water-soaked area of the blossom end of the fruit. Blossom-end rot is a complex disorder, which is thought to be caused by a calcium deficiency. However, the solution is not often as simple as adding calcium to the soil.

High temperatures and wind, fluctuating water availability and a little drought stress thrown in (sounds like Oklahoma) create an environment in which you may see blossom-end rot. Somewhat ironically, excessive soil moisture for a long period of time can also contribute to this problem, as it tends to damage the root system and diminish the plant’s ability to uptake calcium. Excessive fertilization with nitrogen can also be a contributing factor.

Just remember, calcium deficiency is rarely a direct cause of blossom-end rot. It is similar to how a fever is an indicator of a problem and not the actual problem. Adding calcium can be of little value if the blossom-end rot is the result of environmental conditions mentioned above.

These are only two of the many challenges we face growing tomatoes. You can find several relevant fact sheets on the topic by visiting the Lawn & Garden page of our website, tulsamastergardeners.org, and then clicking on “vegetables.”

Garden tips

• Vigorous, unwanted limbs should be removed or shortened on new trees. Watch for forks in the main trunk, and remove the least desirable trunk as soon as it is noticed.
• Most varieties of mums are more productive if “pinched back” now. Either pinch off with fingers or cut to remove an inch or so of limb tips above a leaf. This results in the growth of new limbs and a fuller plant. Do not pinch after mid-July or it will interfere with fall blooming.
• Watch for tiny, sap-sucking insects called aphids on roses, perennial flowers, shrubs and vegetables (especially tomatoes). They produce a sticky substance called “honeydew." Many can be dislodged with a hard spray from your garden hose or two applications of insecticidal soap will usually greatly reduce any aphid damage to your plants.
• Crapemyrtles are one of the few shrubs that should be planted in the middle of summer. Growth of new roots of these plants occurs best with summer soil temperatures.

Summer Challenges for Your Gardens

Protecting your garden from summer temps

Allen Robinson: Ask a Master Gardener

Sunday, June 10, 2018

Q: It seems to be getting hotter earlier each year, and 2018 is no exception. What are the most important things I should be focused on to ensure a successful lawn and garden season throughout the summer? Alicia M., Broken Arrow

A: Hot and dry days of summer not only put a stress on people, but also on yards, plants and gardens. Like people, keeping them healthy is the best way to prevent diseases and other problems. Proper weeding, mulching, fertilizing and watering will go a long way to help create and maintain a healthy landscape.

Weeding: Nobody likes to weed, but it’s a necessity. The key is to apply pre-emergent herbicides at the proper time, visit your gardens often and pull weeds as they appear, and to keep gardens properly mulched and lawns properly fertilized. Remember — the best countermeasure to weeds in a lawn is a thick, healthy turf.

Mulching: Mulching protects tree trunks from lawn equipment damage, reduces water loss due to evaporation, keeps the soil cooler in the summer and warmer in the winter, prevents grass and weed growth, adds beneficial organic material to the soil as it decays and, quite simply, looks better. Remember that most plants get oxygen through their roots, not from leaves, and will suffocate without air in the soil. So, a maximum of 2-4 inches of a loose material, such as shredded tree bark, wood chips or compost from your own compost bin, is sufficient. The desirable mulch pattern should look like a doughnut around the trunk, not a volcano.

Fertilizing: Having a soil test conducted is the best way to know exactly what your lawn and gardens need. A test should be done about every three years. In general, Bermuda grass needs about 5 pounds of nitrogen per 1,000 square feet each active growing season, applied between spring and fall. So, a good rule of thumb is to apply 1 pound of nitrogen per 1,000 square feet in each of the five months between and including April and August. Fertilizing after August will increase the chances of spring lawn diseases (e.g. Spring Dead Spot) next year. Fertilize fescue in the spring, then again in September and November. Do not fertilize fescue or any cool-weather grass in the summer.

Watering: Watering more infrequently and longer is preferred over watering often and shorter. This method allows the moisture to go deeper into the ground, thus coaxing roots to do the same. By doing this, your lawn will sustain itself through hot/dry conditions much better. Generally, the equivalent of 1 inch of water per week is sufficient. If it’s very hot and dry, up to 2 inches per week may be necessary. Water early in the morning to avoid heavy evaporation and to give the plants a chance to dry off before nightfall. For gardens, drip irrigation is the most efficient way to water.

Garden tips

• Renovate overgrown strawberry beds after the last harvest. Start by setting your lawnmower on its highest setting and mow off the foliage. Next, thin crowns to 12-24 inches apart. Apply recommended fertilizer, pre-emergent herbicide (if needed) and keep watered.
• White grubs will soon emerge as adult June Beetles. Watch for high populations that can indicate potential damage from grubs of future life cycle stages later in the summer.
• Thatch is a layer of dead and living stems, shoots and roots that pile up on top of the soil at the base of lawn grasses. If it is over ½-inch thick, it should be removed with either a core-aerator or power-rake. Now is the time to de-thatch Bermuda and zoysia. De-thatch fescue, if needed, in the fall.

Match Plants for your Soil and Weather Environment

Selecting the Proper Plants for Your Gardening Conditions

Tom Ingram: Ask a Master Gardener

Sunday, May 27, 2018

Q: I am planning on making some improvements and enhancements to my garden this year. With so many options, how do I decide which flowers and shrubs would be best for my garden? DS

A: The first thing to consider is the sun. A site would be considered full sun if it gets 6 or more hours of sunlight each day. Part sun would be 4-6 hours and shaded would be less than 4 hours of sunlight per day. Almost every plant you consider is going to have a sun rating on its tag. Pay attention to it. If you purchase a plant that wants full sun and you place it in a shady location, it will not thrive, may not bloom and may not even make it.

When considering the sun, also consider environmental hot spots, such as along a wooden fence or against the house. These structures can decrease circulation and increase ambient temperature to the point only the strongest can survive.

If you are considering a location close to the house, take into consideration which side of the house. The north side tends to get less sun. The east gets primarily the cooler morning sun. And the south and west sides will get the sun in the hottest part of the day, so plant accordingly.

Soil type is another important consideration. Do you have sandy soil or a more clay-like soil? Sandy soils will drain quicker, where clay soils will retain water. Some plants will specify “well-drained soil.” If you have something you want to plant in a location with clay soil that requires well-drained soil, you will need to amend the soil to increase drainage. Or plant something that can tolerate wetter conditions.

Speaking of water, many plants will come with watering recommendations. Take that into consideration as well. If you purchase a plant that needs a lot of water in a location that gets full sun, plan on spending part of your summer watering.

Soil chemistry is another factor to consider, as some plants, like azaleas, prefer a more acidic soil. A soil test is always good to be sure.

One way to get ideas for your garden is to look at other gardens. Knowing this, the Master Gardeners have our yearly garden tour coming up June 9 and 10. On the tour this year, we will have five Master Gardener gardens (plus our demonstration garden at the Extension office) to tour. We have been working hard this spring to make them beautiful for you. In addition, one of the homes will have lectures throughout both days on a variety of topics, such as environmentally friendly gardening, succulents, annuals and perennials for the shade, azaleas, landscape design 101 and monarch butterflies. Visit our website at tulsamastergardeners.org for more information and to purchase tickets.

Garden tips

• Plant warm-season vegetable crops, such as watermelon, cantaloupe, cucumber, eggplant, okra, sweet potatoes, etc., now.
• Fruit trees, especially apples and peaches, must be thinned out for best production. Prune apples 4-6 inches apart and peaches 6-8 inches. This will ensure larger fruit and less damage to limbs. If not thinned, the tree's resources will be used to such an extent that next year’s crop will suffer.
• Late May is the best time to control borers in the orchard. Contact OSU Tulsa Master Gardeners for fruit tree spray recommendations.

Attracting Monarch Butterflies to Your Garden

Attracting Monarch Butterflies to Your Garden

Brian Jervis: Ask a Master Gardener

Sunday, May 13, 2018

Q: I am intrigued by the beautiful butterflies that are around Tulsa each year but know very little about them. Could you tell me how I can attract them to my garden? Melissa H., Tulsa

A: Most of us would agree with you that butterflies are such a visual blessing to our gardens. They are beautiful and do wondrous work in the pollinating world. Two of the most common types of butterflies in our area are monarchs and Black Swallowtails (the Oklahoma state butterfly).

Food is obviously an essential part of their life cycle, but they are somewhat picky eaters and will feed exclusively on particular plants, called host plants. Having these plants available will not only draw butterflies in to lay their eggs, but also will allow you to watch the development of the caterpillars. One of the keys to having beautiful monarch butterflies around your garden is having lots of milkweed. Monarch caterpillars feed exclusively on milkweed (Aesclepias) and cannot survive without it. With almost 20 different species of milkweed native to Oklahoma, you’re sure to find some that fit your garden area. When planting milkweed, be sure to plant multiples (three to five or more). A single plant simply will not be sufficient for monarchs as they are eating machines. If you want lots of monarchs, plant lots of milkweed. Planting milkweed is a great way to help other pollinators too, as the plant provides valuable nectar resources to a diverse suite of bees and other butterflies. Other nectar sources include marigolds, petunias and asters. While milkweed is a beautiful plant to look at, be sure to keep milkweed sap out of your eyes as it can be irritating. Caterpillars of the Black Swallowtail feed on parsley, dill and fennel. So, if you garden with these, plant enough for you and the caterpillars.

A few key tips to coax these beauties to your yard include providing “roost” stations for them at varying heights and protection to shield them from wind and predators. They are attracted to plant color, structure and height. Provide moist areas with shallow puddles to encourage gathering. Butterflies are cold-blooded and enjoy warming themselves in the sun so provide rocks or exposed soil that will warm to the sun’s exposure. Use few, if any, insecticides as they can easily kill good insects, along with bad ones, and no bug zappers please.

Because of modern changes, habitat destruction and shifting land management practices (suburbanization), there is a lot less milkweed today than previously. This has caused a decline in monarch butterfly populations and numbers to be at an all-time low for the past two overwintering seasons. Many pollinators are declining as well. By planting milkweeds and nectar plants for adult monarchs and pollinators, you can help maintain the monarch migration and sustain the pollinators whose pollinating services maintain our ecosystems.

Monarchwatch.org is a terrific resource to learn more about monarch butterflies and milkweed. Also, consider attending a free seminar called “Monarchs, Milkweeds and More” on May 26 at the Tulsa fairgrounds, hosted by the Tulsa Master Gardeners. Detailed information can be found at tulsamastergarders.org.

Garden tips

• Clean out water garden and prepare for season. Divide and repot water garden plants. Begin feeding fish when water temperatures are over 50 degrees.

• Plant warm-season vegetable crops, such as watermelon, cantaloupe, cucumber, eggplant, okra, sweet potatoes, etc., now.

• Fruit trees, especially apples and peaches, must be thinned out for best production. Prune apples 4-6 inches apart and peaches 6-8 inches. This will ensure larger fruit and less damage to limbs. If not thinned, the tree's resources will be used to such an extent that next year’s crop will suffer.

• Late May is the best time to control borers in the orchard. Contact OSU Tulsa Master Gardeners for fruit tree spray recommendations.