Frequently Asked Questions
Spring | Summer | Fall | Winter
Spring - March, April, May, June
Bulbs - Transplanting
Q. When is the best time to move Bulbs and what procedures should I follow to get this done successfully?
A. Allow your bulbs to complete their growth cycle without disturbance. Once they flower, remove spent blooms, but permit their foliage to mature and die back on their own accord. Keep containerized bulbs vigorous with timely watering and regular fertilization with a water-soluble fertilizer applied about every two weeks. Once the leaves begin to die, stop fertilizing and reduce water. When the foliage is dead, dig the bulbs, store them in a cool dark spot with good ventilation, and plant them in their new home next fall.
Chip Tynan, Missouri Botanical Garden
Lawns
Q. What cause the round dead patches of grass on my cool season lawn? Is it dying and if not what can I do to control it?
A. Your problem is known as Brown Patch and is caused by a fungus. It is one of the most prevalent diseases in warm humid areas, attacking many types of turf grass. When the infection is severe and warm weather continues, the disease attacks plant crowns and kills eventually the grass. This can be controlled with Chlorothalonil, a preventive fungicide sprayed in mid June, or a curative spray as soon as symptoms appear. Read and follow label directions.
Vegetables - Tomatoes
Q. Why do I have these crusty round cracks on the top of my tomatoes?
A. Tomatoes crack when certain environmental conditions encourage rapid growth during ripening such as drought followed by heavy rain or heavy watering. This can be eliminated if you maintain even soil moisture with regular watering and mulching.
Q. My tomatoes have large brownish black soft spots on the bottom of them. Can this be fixed now so I will be assured of having a crop this year?
A. You have what is known as Blossom end rot and your first choice of action should be to obtain a soil sample to make sure your ph is what it takes to grow healthy tomatoes. To prevent future blossom-end rot continue to maintain uniform soil moisture, avoid using high-nitrogen fertilizers or large quantities of fresh manure, plant in well-drained soil, and do not cultivate more than 1 inch within 1 foot of the plant.
Fruit - Peach Trees
Q. The leaves on my peach tree are starting to grow but they are all thick and curled up.
A. Leaf curl is caused by a fungus that attacks peaches wherever they are grown. Infection occurs as soon as the buds begin to swell in the spring. Fungal spores are splashed from the bark to the buds by spring rains. Infected leaves can't be cured. To prevent recurrence of the disease the following year use or spray a Multi-Purpose Fungicide in early spring or late fall.
Fruit - Apple Trees
Q. I noticed that the leaves on my Apple tree have what seems to be a white powder all over them. Is this something to worry about?
A. Your problem is what's known as Powdery mildew that is caused by a fungus that thrives in both humid and dry weather. The fungus spends the winter in leaf and flower buds. In the spring spores are blown to the new laves, which are very susceptible to infection. Powdery Mildew thrives in warm days and cool nights, reduced light and lack of rainfall. Spray infected trees with a fungicide containing myclobutanil or sulfur.
Insects - Bagworms
Q. What can I do to bring my Bagworm problem under control and get rid of them?
A. The best control for bagworm is to remove and destroy the bags as soon as they appear. Any bags left on the tree will provide a source of insects for subsequent years. Some species of birds are able to open the bags and feed on the larvae. Bagworms are controlled chemically, but the treatment must be done the end of May to early June as soon as the eggs hatch, and the larvae begin emerging from the over-wintering bag. Chemical control becomes much less effective once the larvae get larger and more protected in their bag. Recommended chemicals are Bacillus Thuringiensis (Bt) and spinosad.
Summer - June, July, August, September
Insects - Aphids
Q. Something in my garden is distorting plant and vegetables leaves and some of them feel sticky.
A. Your problem may be Aphids. They are extremely prolific and populations can rapidly build up to damaging numbers during the growing season. Damage occurs when they suck the juices from the leaves and buds. They are unable to completely digest all the sugar in the sap and they excrete the excess in fluid called honeydew which is the reason your leaves feel sticky. Spray with insecticidal soap or an insecticide containing acephate. Read and follow label directions.
Perennials - Hydrangeas and Roses
Q. I have some well-established Hydrangeas that have been fine until this year. Can you tell me why they didn't bloom?
A. There are several reasons why they didn't bloom:
1. Extreme cold weather could have killed the buds.
2. Pruning at wrong time will remove potential buds.
3. Too much shade will hinder flower growth.
Try to do the following:
1. Plant hydrangeas in a protected spot in the garden.
2. Prune hydrangeas after they have finished blooming by cutting back the longer branches.
3. Expose the plants to brighter light by pruning away some of the surrounding vegetation or transplant them to a location that receives filtered or half-day sun, in cool-winter areas, in full sun.
Q. My Roses have circular black spots with fringed margins on the upper surface of the leaves. What can I do?
A. Black spot is caused by a fungus that is a severe problem in areas where high humidity or rain is common in Spring and Summer. The spores are spread from plant to plant by splashing water and rain. The fungus enters the tissue, forming pinhead size spots. As the fungus spread the spots get bigger and the twigs are in danger. Spray them with a fungicide such as Chlorothalonil (Daconil), Captan or Mancozeb as soon as leaves emerge. Continue this into October on regular intervals immediately after blooming. Don't wait much later than that, as next year's flower buds are formed on the new growth of the current season.
Crabapple Trees - Red Cedar - Shrubs
Q. I have some small yellow spots, large orange spots and tiny black spots on my Crabapple tree. Some of the leaves are also beginning to fall off.
A. Your tree has Cedar-apple rust that is caused by a fungus that affects both Crabapples and certain species of Juniper and Red Cedar. This disease cannot spread from Crabapple to Crabapple, or from Juniper to Juniper, but must alternate between the two. In the Spring, spores from brown and orange galls on juniper or cedar are blown up to 3 miles to Crabapple Trees. During mild, wet weather, the spores germinate and infect the leaves and fruit, causing spotting and premature leaf and fruit drop. During the summer, spores are produced in small cups on the underside of leaves. These spores are blown back to Junipers and Cedars, causing infections. Cedar-apple rust cannot be controlled on the current season's foliage and fruit. In the Spring spray the trees with a Fungicide such as Mancozeb, sulfur, or miclobutanil (Immunox).
Fall - September, October, November, December
Protecting Vegetables and Berries from Animals - Birds, Rabbits, Gophers, Deer, Possums, Ground Squirrels, Rats and Mice
Q. Is there anything that can be done about pesty animals?
A. To keep Birds away from berries, create a wire or metal frame around plants. Over this drape netting with ¾ inch mesh. The size lets in air, water, and sunlight. Secure netting at the bottom so berry predators cannot slip underneath.
One method to deter Rabbits from feeding is to create a 24-inch fence. Since rabbits can burrow underneath fences, you will have to extend the wire mesh at least 6 inches below ground.
Fencing is the only method of keeping Deer from feasting on your property. To totally exclude Deer, install a traditional fence that is no less than 8 feet high.
In some areas, regulations protect ground squirrels, so contact and consult with the Wildlife Damage Biologist, Missouri Department of Conservation at 816-759-7305 before using traps or poison. Without restrictions they can be trapped and released in a more appropriate surrounding where they will not do more harm.
Rats and mice can be poisoned or you can purchase a couple of mean cats. Make it a point to keep them away by keeping your yard clear of debris which includes trash piles, leaves, firewood, newspapers, boxes, pipes, logs, old doghouses and tree cutting. Anything that must be stored outside should be kept on platforms 12 to 18 inches off the ground.
Trapping and relocating is the only sure fix for Possums, Raccoons and Gophers.
Trees - General Pruning Question
Q. When is the time to prune ornamental trees?
A. Dead wood on trees and shrubs can be removed at any time of the year, so now would be appropriate to remove this material from Japanese maple. Removal of live wood should be done thoughtfully. Because there are so many unique varieties of Japanese maples, there is no single "classic" form or shape that all should be trained to. Each tree should be viewed on an individual basis.
Since Japanese maples bleed from cuts made in live wood, major pruning should be done late in the dormant season, just prior to spring growth. Bradford pears and Crabapples can be handled either of two ways. If they are viewed as fruit trees, they can be pruned in the dormant season before flowering. Sometime in February or early March would be ideal. Of course, this will result in the loss of some spring flowers. If viewed as flowering ornamental, they can be pruned immediately after blooming. Don't wait much later than that, as next years flower buds are formed on the new growth of the current season.
Prune young Birch trees for shape during their formative years, but avoid heavy pruning of older trees as they are subject to decay from large wounds. Birch trees also tend to bleed after pruning. "Oozing" can be minimized by pruning them from late summer (after mid July) to early winter rather than late winter and early spring.
Chip Tynan, Missouri Botanical Garden
Soil - Testing and Amending
Q. How can I obtain a soil test?
A. A soil test can be done with one of the do-it-yourself kits if testing for the soil's pH as well as nitrogen, phosphorous and potassium. For a more through analysis, contact your County Extension Office.
Q. What can I use to best amend this Missouri clay soil?
A. Organic matter that has decayed and compost make a good combination for amending Missouri's clay soil. If done in the Fall, leaves can be crushed and also added by turning or tilling them into the soil. This will give them time to totally decompose over the winter. You must add an amendment layer 1 to 4 inches deep to effect a change in soil structure. Any leaves left over from the fall drop can also be crushed and used as mulch during the growing season. The one thing to remember is to make sure everything used is broken down and you're not tilling in or turning under any raw material.
Perennials - None in particular
Q. Why do so many of my Perennials look like they're not doing anything.
A. That look is called natural dormancy. Many perennials and all bulbs undergo a period of no growth, which usually occurs soon after they have flowered. Although the plant may seem to be inactive during this period, it is actually developing roots, bulbs, or rhizomes for the following year's growth. The foliage of many perennials and bulbs eventually dies back completely, and the plant becomes entirely dormant.
Putting Roses to Bed
Q. What is the best time and how do I prune Roses?
A. Pruning in some instances will depend on the cultivars. Some roses are best pruned in the spring after all chance of frost has passed. Some roses are cut back in late fall to about 18 to 24 from the ground in order to minimize the risk of cold weather injury from strong winds, ice loads and heavy snow. Climbers are normally pruned slightly earlier in late winter as the buds begin to swell. Winter pruning of climbers consists mainly of the lateral shoots that grow out from the main canes to 2 or 3 buds each. Main canes can be shortened by 1/3 to ½ after the first bloom. Plants 3 years old or older should have one or two of the oldest thick canes removed at ground level once a year.
Winter - December, January, February, March
Houseplants - None in particular
Q. My plants seem to be dying, the leaves feel sticky and I haven't done anything different from the past years that I've had house plants.
A. It appears that you have scales, mealy bugs or aphids that are living on the underside of the leaves. Isolate it from the other plants and spray with insecticidal soap or wash the plant with soapy water, (2 teaspoons of mild detergent per gallon of water) while rubbing the underside of the leaves with a soft cloth or cotton balls.
Insects - Asian Beetles
Q. I have an army of "lady bug looking" creatures all around my windows, on my window sills and some are even flying around the house.
A. Your creatures are Asian Beetles. They're congregating around your windows attempting to keep warm after evolving from their winter hibernation. Inside the house suck them up with your vacuum cleaner and release them outside, preferably in a sheltered area well away from the house. In some cases a household aerosol spray containing pyrethrins may be used. To help control them on the outside, an insecticide containing carbaryl (sevin) can be used. Read and follow label directions.
Pests - Moles and Voles
Q. I know I must have Moles because my grass has raised and sunken areas. What will get rid of them before they tunnel enough to do serious damage to the roots of my lawn?
A. Trapping is the single best way to reduce mole populations. Traps are available from most hardware stores, seed catalogs, or farm and garden centers. Set them in fresh, active runs, carefully following the manufacturers instructions. If a trap doesn't catch a mole in 2 or 3 days, move it to a new tunnel, as surface runways are only temporary feeding areas that are abandoned within a matter of days. Persistence pays results, but don't expect regular success.
Voles are gnawing mammals and are closely related to mice. In fact, they are frequently referred to as meadow mice. They are about the size of a house mouse, but with much smaller ears, a shorter tail, and a somewhat blunt face. Voles make both surface runways as well as underground tunnels. They often travel via the tunnel systems created by moles. The best control for voles is the use of mouse-sized snap traps. These can be baited with peanut butter and fruit or other nut meats and placed directly in the pathways. A light covering of grass or leaves may increase trap effectiveness. Keeping nearby vegetation regularly mowed will alter the habitat and may reduce their numbers.
Chip Tynan, Missouri Botanical Garden
Trees and Shrubs - This was by far the MOST frequently asked question.
Q. With the weather going from hot to cold and visa versa, my trees and shrubs have started to bud out and some of them are beginning to look dead. Are they dying and if not, why are they looking like this?
A. When sub-freezing temperatures are predicted following a warm period in spring, homeowners are often concerned that ornamental plants in their landscapes may be damaged. While it is rare that we make it to the frost-free date in May without some freezing injury, the damage is generally minor and has no long-term health consequences.
Temperate zone woody plants survive freezing by entering a state of dormancy in late Fall. Cold hardy, dormant plants have the ability to survive extremely low winter temperatures. A dormant plant will not grow shoots even when exposed to an extended period of warm temperature. However, dormancy is gradually overcome as plants accumulate hours of chilling temperatures and, by March, woody plants will often respond to warm temperatures by opening their vegetative and flower buds quickly. In general, the farther advanced the buds, the more sensitive they are to freezing temperatures. The following web site from Michigan State and Washington State Universities describes the relative sensitivity of buds on various fruit trees to cold based on state bud development. http://www.hrt.msu.edu/faculty/langg/Fruit_Bud_Hardiness.html
Occasional freezing injury to flowers on trees and shrubs is something that we Missourians must learn to accept as a consequence of our unpredictable spring temperatures. Just think how much more we appreciate our Magnolias and peaches when they come through un-frosted than do folks in parts of the country not subject to our wild Spring temperature swings.
