Native Azaleas

Question: My neighbor has a type of azalea that has a light pink bloom, it is very fragrant and it does not have leaves on it yet. Do you know what kind of azalea this might be?

Answer: As a group these are called deciduous azaleas and are most likely native species. Although there are many native species of Azaleas the one your neighbor has is likely Rhododendron canescens, the Piedmont Azalea. Native azaleas such as the Piedmont Azalea, often called wild honeysuckle bush, are at least as beautiful as their non-native evergreen cousins and are much more fragrant. As a group they are greatly underused in the southern landscape. Some have unusual yellow to orange and orange-red flowers, such as the Florida Flame azalea. Most of them are either native to Alabama or will grow well in most areas of the state. The individual florets are trumpet shaped and usually borne in large terminal clusters. The sweet smelling blooms have led to the common name, wild honeysuckle bush. Identification of native azaleas can be difficult because of the similarities between species. Natural hybridization has complicated the matter by producing many intermediate forms with unusual flower colors.

Many southerners first encountered native deciduous azaleas while walking in the woods. There they may have spotted the pink, fragrant, delicate flowers of the Piedmont azalea mentioned above or the orange-yellow blooms of the Florida Flame azalea (Rhododendron austrinum). Maybe it was the white, yellow- blotched and lemon scented flowers of our namesake Alabama Azalea (Rhododendron alabamense). Alabama Azalea while not the showiest flower may be the most fragrant of all the native azaleas.

Deciduous azaleas prefer moist, sandy, well-drained soil. Morning sun with afternoon shade will enhance blooming and reduce excessive drying. Pine straw or pine bark mulch should be added to protect the shallow root system. A light application of slow release azalea fertilizer just after blooming should be sufficient to keep them growing and blooming. If your soil is not well drained consider planting on a raised bed or individual mounds.As landscape specimens, in woody areas, deciduous azaleas are a wonderful addition to any landscape. They do best when left unpruned and allowed to maintain an open natural habit. Deciduous azaleas are not always available in nurseries but ask for them and this will encourage nurseries to stock a wider selection. Some plants that may be more readily available are native hybrids that were developed for superior quality. A friend of mine in Mobile, Tom Dodd, III has developed several of these hybrids that he calls the Confederate series. These hybrids are well adapted to our climate, have larger blooms than the native azaleas and they're all fragrant. Some names to look for in this series include 'Admiral Semmes' that has big, fragrant yellow flowers and 'Col. Mosby' with large fragrant deep pink flowers that fade to light pink with a yellow blotch. At the front door of the Birmingham Botanical Gardens, General N.B. Forrest is now in full bloom. It has large ruffled, red-orange blooms in clusters that show off in late April. If you want to look at pictures of these and other great native plants go to the Dodd Natives site.

Asian Lady Beetle

Question: My house has been invaded by lady beetles. They are coming out of the wall by the hundreds. Why are they here and what can I do about them?

Answer: Lady beetles are normally considered beneficial insects because they feed on pest insects such as aphids in gardens and landscapes. However, the multicolored Asian lady beetle (which is the one you have) can become a serious household problem. These beetles have been reported to congregate on the sides of buildings by the thousands. They will move inside if given the opportunity, and will stain carpeting, wallpaper, and anything else and they stink badly when crushed. However, these beetles are not poisonous, do not sting, are not carriers of disease, and do not eat wood.

The Asian lady beetle was originally released as a biological control agent for pecan aphids in California. They have a very wide host range and can feed on rose, apple, poplar, conifer, and crape myrtle aphids. Although they can be a nuisance overall they are quite beneficial.
The beetles seem to be attracted to light, reflective surfaces such as large windows, or light-colored walls and trim. Beetles usually are found on the sunniest areas of buildings. In Japan, Asian lady beetles overwinter in the cracks and crevices of mountain rocks. In the United States, they use buildings as protection from winter. They seem to be attracted to blue and gray colors that look like the mountainous rocks in their native habitat. The beetles begin to invade homes through cracks and crevices during the fall (around October or November in Alabama). People with log homes may find this beetle particularly troublesome due to the beetles' preference to dwell in cracks and crevices. Common overwintering sites include door and window frames, porches, underneath siding, roof shingles, wall voids, attics, and soffits.

This time of year, as the temperature increases, so will beetle activity. They have been in your home all winter and now are looking for a way out. As they try to escape, beetles can be found along large glass windows and in light fixtures because they are attracted to light, and around doors, baseboards, and drop ceilings.

Control involves a multi-pronged approach. Prevention is the key to keeping this lady beetle from getting into homes. A space less than 1/8 inch will allow lady beetles entry. To prevent entry you can use many of the same techniques that can save you energy as well: Caulk cracks along windows, doors, or other portals of entry. Seal and screen attic vents and install tight fitting door sweeps. Gaps under glass sliding doors may be sealed with foam weather stripping. Also, seal utility openings such as pipes, dryer vents, and cable TV wiring ports, with caulk, steel wool, or other mesh.

Once they are indoors chemicals are generally not recommended. The beetles have to be sprayed directly or walk over treated surfaces to obtain a toxic dose. Vacuuming or sweeping is the first line of defense. Do not crush the beetles as they can stain and they smell horrible. If you can empty the vacuum contents or sweepings outside some of the beetles may survive and pay you back by eating some of the bad bugs in your garden this summer.

Original photo by: Timothy J. Gibb, Extension Entomologist, Department of Entomology, Purdue University

Spring Lawn Care in the South

Question:
I have a lawn weed problem and I was wondering if I should use a weed killer and herbicide blended product?

Answer:
The so called “crab grass/weed preventer with fertilizer” products are marketed as convenient to use but that convenience may come at a price. The first cost is the product itself which can be quite expensive. Another cost may be the decreased health of your turf. Those products which contain fertilizer plus pre-emergent weed killers must be applied before warm season weeds (like crabgrass) germinate, which may be in mid to late February, in order to effectively kill those weeds. Unfortunately, that is much too early to apply fertilizer for all grasses except fescue or bluegrass. When fertilizer is applied that early the grass may start to grow much too soon if we have a couple of weeks of warm weather. Past experience has taught us (remember the Easter weekend freeze of 2007) that a late frost can do a lot of damage to warm season turf grasses. Bermuda, Zoysia, Centipede and St. Augustine grass are all tropical grasses that are much better adapted to heat than cold. These grasses can be easily “tricked” into growing too early in the spring. This can be true for any warm season grass but according to Jim Jacobi, Extension Pathologist, it is especially damaging to Centipede grass.

The more prevalent “weed and feed” products have a fertilizer plus a post-emergent weed killer. These products are normally applied to young developing weeds. In most years these weeds are most susceptible to herbicides during the same time the grass is in the “green up” stage. This is the correct time to fertilize but it can be a very bad time to apply herbicides. The reason it can be bad is because warm season grasses are most easily damaged or stressed at this stage of their growth.

You may be wondering if there is a correct time at all to use “weed and feed” products and that is a very good question. Those products that contain a post-emergent weed killer and fertilizer blends may have a window of usefulness after spring green up when late germinating summer weeds are small. For instance, if you use a pre-emergent weed killer (without fertilizer) in mid to late February it may wear off enough that some later weeds emerge. These weeds could be controlled with a “weed and feed” in late May or early June after the grass has past the stressful green up phase.

There is a correct way to approach weed control and proper fertilization but it involves an extra bit of effort. Pre-emergent weed killers may be used by themselves at the time just mentioned and fertilizer should be applied by itself in late April to early May. Fertilization type and amounts should be based on soil test results not guess work and this is a good time to have a test done to add lime if needed and find the correct fertilizer for your lawn.

I have had people tell me they have done it the “wrong” way for many years without a problem. My response has always been I know people who live very unhealthy lifestyles and live to a ripe old age but we seldom hear about all those who die young because the former is the exception not the rule. For instance, we regularly see soil test reports with excessively high amounts of phosphorus and potassium. These lawns may go for a long time with no problem but problems may arise at some point down the road. Even if you never see severe problems you are at the very least wasting fertilizer and possibly polluting ground water, streams and rivers. Also, we regularly see lawns that are fertilized too early get hammered by a late frost. If you fertilize too early the law of averages will eventually catch up with the luckiest gardener. Lastly, we see turf with unexplained lack of vigor and poor health problems that may have been severely weakened by a poorly timed herbicide application. For information on proper care of your turf grass visit the publications area with the Alabama Cooperative Extension System.

Pyracantha

Question: Can you suggest a good screen plant that will deter people from easily accessing my back yard? I do not want a fence but would like a little added security.

Answer: The plant that pops up in my mind is a pyracantha. Winter is often when I think of this plant because it has showy fruit until the cedar wax wings and other birds clean them off. Pyracantha is a member of the rose family and, like its cousin, has an abundance of thorns. The thorns are much larger and more painful to encounter than roses. My dad always said nothing will keep determined intruders out, but pain will do a good job deterring ‘honest’ folks.
Although pyracantha can be maintained as a four or five foot shrub, it would be better if you did not have to prune it very often due to the aforementioned pain. The ultimate size of most varieties will be about 10’ by 10’, so it does not take many plants to make a living fence. The plants can be planted somewhat closer for quicker fill but remember to allow plenty of depth for them to spread. They are fast growers that are adapted to many soil types, except poorly drained soil.

Winter is a great time to plant them. Dig the plant hole as wide as practical but at least twice as wide as the root ball. To avoid plant settling to a position deeper than desired, do not dig any deeper than the root ball. I always like to pull the plant from the container and wash off most of the bark from around the roots. This will allow you to spread the roots out laterally in the wide planting hole and will prevent air pockets which would develop when the bark slowly decays after planting.

The first year after planting pyracantha will need supplemental watering to get them well established, but once established they are pretty tough plants. Keep the area around the plants weed free and do not use weed eaters around the base. Three inches of mulch over the root system can go a long way in helping control weeds and retain moisture. Do not pile mulch thickly around the base of the plants.

Although pyracantha is not a native plant it is widely adapted and the native birds and wildlife do love the fruit they produce. Pyracantha can also be used in floral arrangements to add a splash of color and a distinct texture. Most varieties have bright red berries but there are some yellow and orange fruited varieties available. If the standard sized plant is too big for the area you have in mind there is a compact selection called Red Elf. This might be a good choice for underneath a window to deter an intruder or peeping Tom.Two serious problems on pyracantha are fire blight, a bacterial disease that can kill the plant, and scab, a fungal disease which causes defoliation and turns fruit a dark, sooty color. To minimize problems, choose disease-resistant selections such as ‘Apache,’ ‘Fiery Cascade,’ ‘ Mohave,’ ‘Navaho,’ ‘Pueblo,’ ‘Rutgers,’ ‘Shawnee’ and ‘Teton.’ For further information on growing this useful and beautiful plant visit here.

Mistletoe

Question: Can you tell me about the harmful properties of mistletoe and whether or not it is poisonous to people?

Answer: Mistletoe is an interesting group of plants with an interesting history. On a worldwide basis mistletoe may generically refer to any of more than 200 species of semi-parasitic shrubs found worldwide. However, according to Curtis J. Hansen, Curator Freeman Herbarium, Auburn University there is primarily only one species of mistletoe that dominates the eastern United States and that is the “Oak Mistletoe”, or scientifically speaking, Phoradendron leucarpum. It sounds very romantic in Greek but literally means "tree thief". Maybe that’s where the idea of “stealing” a kiss under the mistletoe originated.

All mistletoes are parasitic, meaning they grow into a host tree and "steal" nutrients for growth. However, they are also green, so they can produce some of their own nutrients through photosynthesis. While most mistletoes don't outright kill their tree-host, they can weaken them over time and ultimately be the cause of tree death. As the name indicates, Oak Mistletoe is found mostly in oak trees, but may also be found in other hardwoods. This particular species isn't known to grow in pines or conifers in our area. Mistletoes are particularly easy to spot at this time of year when the leaves of the hardwood trees have fallen. In fact, you may find many plants in full fruit with little white berries, for female plants and male plants that are in full flower. There are separate female and male plants within this species.

The parasitic properties of mistletoe are often duplicated by the men I see hovering around the sprigs at Christmas parties. Rather than true roots, the plant has extensions called holdfasts that grip the host plant. With the holdfast the plants take what they want from the host plant (again not unlike the aforementioned men).

In the South, tiny yellow flowers bloom on the evergreen mistletoe from fall into winter. The familiar white berries begin to form soon after pollination and resemble little packets of glue around tiny indigestible seeds. Although eating mistletoe berries may potentially be lethal for humans, birds seem to be immune to any toxicity.

The immunity of birds to mistletoe's poisonous qualities is essential to the welfare of the plant. The dispersal and propagation of mistletoe is largely dependent on birds that eat berries but do not digest the seeds. Studies suggest that seeds are most likely to survive and grow if a bird deposits them on the same species of tree on which the parent plant lived.
The use of mistletoe as a romantic lure stems from England at least as early as the 1500s. A version of the tradition persists today in secular Christmas decorations. Mistletoe has an interesting story behind its name. Several hundred years ago, it was thought that the mistletoe plant was formed spontaneously from bird droppings. Of course no one thought to look inside the bird droppings for a concealed seed. However, due to this error, the plant was given the name mistletoe which translates literally in English to “dung-on-a-twig.” I think we should stick with the name mistletoe because “meet me under the dung-on-a-twig” just doesn’t set the right festive mood.

Choose a Christmas Tree

Question: I love to use a real Christmas tree but the needles are always a mess. What type tree has the least problem with needle shedding?

Answer: The quick answer is "the fresher the tree, the better it will hold its needles." The only way to know you have a freshly cut tree is to cut it yourself, or in my case, I just point to the tree and tell one of my sons to cut it for me. If you buy a tree from a local "choose and cut farm," it probably doesn’t matter what species you purchase. The key to keeping the needles attached is to get the fresh cut tree stump into water as quickly as possible.

Choosing a pre-cut tree from a sales lot can be a little riskier than cutting the tree yourself, but if you follow these tips your chance of getting a good tree will improve greatly. Purchase a tree as soon as trees are available even if you don’t plan to decorate it for several days. The sooner you can get the tree in water the longer it will last. Most of the trees on sales lots were cut at the same time, so the longer they stay on the lot without water, the less likely the y will even take water up when they are placed in home tree stands with water reservoirs. Look at the tree trunk near the base and if you see splitting, the tree most likely has dried so severely it will not absorb water.

Look for a tree with a healthy, green appearance and few dead or browning needles. Run your hand along a branch to see if needles seem fresh and flexible. Needles should definitely not pull free easily. If possible, bump the base of the tree on the ground. You should expect some of the old dead needles to fall off, but if green needles also fall off, the tree is not very fresh.

Once you have chosen that perfect tree and have arrived back home safely, you should make a fresh cut a couple inches above the original cut. This removes any clogged wood that would prevent water uptake. If you are not ready to place the tree indoors you may store in a shady area outdoors or in an unheated room or basement. Regardless of where you locate the tree, make sure to check the water reservoir frequently and keep it filled a couple inches or more above the tree’s base. I have not seen any research that proves any concoction added to the water works significantly better than plain tap water.

Another tip to consider involves tree location in the home. Keeping the tree away from heat sources such as air ducts, wood stoves, and fireplaces will prolong the freshness and reduce the risk of fire. Make certain all lights and extension cords are in good working order and turn lights off when the tree is not attended. Because our homes are much drier in the winter when the heating system is operating, a small room humidifier can be good for you, your house plants and Christmas tree.

Some trees are just naturally better at retaining their needles. Douglas fir, Eastern White Pine, Fraser fir, Leyland Cypress, Scotch pine and Virginia pine are considered to have excellent needle retention. Freshness, however, is the key to needle retention.
If you would like some additional tips and a list of the pros and cons of the most popular species, click here.

Winterizing Warm Season Grasses is a No No

Question: The lawn care company recently applied an application of “winterizer” fertilizer to my Bermuda grass. Do you recommend winterizer fertilizer on warm season grasses?

Answer: If this is a well established lawn it is doubtful you need a fall application of fertilizer unless a soil test indicated a low level of potassium. Unfortunately, there are many products on the market sold as winterizer fertilizer. Cool season grasses such as fescue do most of their growing in the fall and spring and they need nitrogen to grow. However, many of these products are also used on warm season grass. Fall nitrogen application can be damaging to warm season grasses. Instead of increasing the cold hardiness, the opposite effect results. A warm fall will lead to continued vegetative growth which sets the plants up for cold damage. Check with your lawn care company and ask for the analysis of the fertilizer used. If the first number is 5% or below, it probably won’t hurt but it would be better if no nitrogen is applied to Bermuda and other warm season grasses after August.

I would suggest you have your soil tested to see if you need potassium or not. If you fertilize during the summer months it is very doubtful extra potassium in the fall will provide any benefit. However, if you do apply fall fertilizer, always apply it onto dry foliage to reduce the likelihood of salt burn.

A soil test provides a wealth of information and can be done for only $7 in Alabama and many state Extension offices offer similar services. Fall is a great time to test the soil because the lab is not as busy and if you need lime you have time to get it out on the lawn before spring growth starts. The lime will slowly move into the soil with winter rains and the pH will gradually rise in time for the first spring growth spurt. Once you receive your test results you may want to contact your local Extension office to talk with a horticulturist about your test results.
I have seen many test results that indicated an excessively high level of phosphorus and potassium. Phosphorus does not leach from the soil very quickly and it can build up to the point that no phosphorus will be needed for many years. Potassium can become so high that it interferes with the uptake of other elements such as magnesium and can result in a lighter green turf color. Also, be aware that an excessively high rate of potassium fertilizer can cause foliar burn.