Vermont Master Gardener is an integral part of the University of Vermont Extension Home Horticulture Program
| Seasonal Tips Archive 2004 |
For archival purposes only. Links, contact names and organizations may have changed.
Answers to popular current questions from the Master Gardener Helpline (1-800-639-2230).
A link is made to those UVM Extension leaflets (EL,GD,etc.) available on the web. All leaflets are available through mail order or in person from UVM Extension offices (see theirPublications Catalog).
Vermont Hardiness Zone Map (link to UVM Extension)
New England Hardiness Zone Map (link to UConn)
POSTED 1/15/04
HOUSEPLANT PESTS: You can often control these pests by cultural practices, such as washing with soapy water (2 teaspoons mild detergent in a gallon of lukewarm water). Rinse with a lukewarm plain water spray. Handpicking of aphids and mealybugs is easy with tweezers or even with a cotton swab or artist's brush wet with rubbing alcohol. These tips and more can be found in leaflet EL38: Houseplant Pests.
HOUSPLANT PROBLEMS: The leaflet OH17: Houseplant Problems provides a chart of common problem symptoms and their possible causes. For instance, tips of leaf margins that are turning brown could be from several causes, including too much or too little water, poor drainage, too much or too little fertilizer, low humidity, drafts that cause rapid loss of moisture. For more information, Leaflet OH 17 can be obtained from the Helpline by calling 1-800-639-2230.
POINSETTIA: If you have the patience and time, you can get your holiday poinsettia to rebloom next year. Here's how:
POSTED 1/29/04
EXOTIC PEST FOUND IN POTPOURRI PINECONES
Below is a website relating to another exotic long-horned beetle that has been found recently in material from overseas. I don't know any more than what is described here and in the website. It sounds like they feed on the cones, not the tree which is a break. The biggest issue is its impact on regeneration. Thought you would all like to know, however.- Margaret Skinner, UVM Extension Entomoligist.
http://www.doacs.state.fl.us/press/2003/12112003.html
ORDERING RESISTANT VARIETY SEEDS FOR LESS TROUBLE LATER ON:
If you need information about growing fruits, go to the Master Gardener Home Page, click on LINKS, click on UVM EXTENSION PUBLICATIONS, Home Gardening, Fruit Culture Leaflets for a collection of 'Fruit Culture Leaflets' to help you along. These include 'Apple Varieties for Vermont', 'Pollinators and Pollinizers for Tree Fruits', 'Dwarf Fruit Trees', and others.
POSTED 2/3/04
FORCING FLOWERING BRANCHES Leaflet OH14: Forcing Flowering Branches contains a wealth of information neatly laid out in chart form. It lists plant types most of us wouldn't even think of on our own, along with the old standbys of forsythia and crabapple. Good 'how to' instructions also included. Bring an early spring into your home.
PLANNING AHEAD FOR DEER PROBLEMS go to Michigan State Cooperative Extension Service website at www.msue.msu.edu/msue/imp/modwl/11209806.html for lists of resistantwoody plants, perennials, annuals, vegetables and more.
PLANNING AHEAD FOR DROUGHT TOLERANCE find plants that have silver or gray leaves (they reflect sun and heat away), thick stems (cacti), aromatic or waxy leaves (lavender), hairy leaves (alchemilla, dusty miller), puffy leaves (sedum), long taproot (eryngium, dill), thick fleshy roots to store water (daylillies, poppies).
Two leaflets that you will have to call the Helpline for:
TEST SEED GERMINATION rate of old seeds by placing some in a moist paper towel placed into a plastic bag. Put the bag in a warm place. Check in a few days for germination. A seed sprouter works well. Just be sure to use only untreated seeds in your sprouter if it is also used for food sprouts.
POSTED 2/26/04
The CYCLAMEN PLANT you received for Valentine's Day can be kept going for years with a little care. While in bloom, feed every other week with a fertilizer for flowers. Give it sun or as bright a light as you can, and constant moisture. The secret to longevity is cool nights, 40s or low 50s. An unheated bedroom is a good place to keep a cyclamen, bringing it out for display only. As flowers and leaves fade, gently pull them cleanly from the tuber with a swift jerk. A fungicide can be dusted in then, to prevent crown rot. When bloom finishes, place plant in a sunny, cool place (60 degrees) and water just enough to keep from becoming bone dry. When night temperatures outdooors are above 55 degrees, repot the corm in a pot 1 inch larger than presently, setting the corm at the same level it was before. As the corm ages, it is more and more above the soilline, until it is up to one third to halfway out of the soil. For the summer, place the plant outdoors in a shady, dry place (under eaves?), and keep barely moist. The old leaves will stay on the plant while the new ones grow in, but the old ones do drop off eventually. Bring your cyclamen back into the cool room when the outdoor temperatures go into the 50's.
TREES THAT ARE TOLERANT OF ROAD SALTS INCLUDE: white ash, oak, honeylocust, white fir and white spruce.
RIVER BIRCH TREES are resistant to birch borer and leaf miner, common problems with white birch trees.
TREES THAT MAKE GOOD LEACHFIELD NEIGHBORS INCLUDE: crabapples, cherries, oaks and pines.
TREES TO AVOID NEAR LEACHFIELDS INCLUDE: maples, willows, poplar and birches. These all take up too much moisture.
GL28: USING DORMANT SPRAYS TO CONTROL OVER-WINTERING PLANT PESTS stresses the importance of timing when applying dormant sprays, which is" before new growth begins in the spring or green tissue is visible, but after buds start to swell". Consider dormant lime-sulfur spray if you have problems with aphids, mites and scale insects. Dormaant lime-sulfur spray is also used to control powdery mildew, rust and black spot on dormant roses. Raspberry and blueberry cane blights can be reduced by lime-sulfur applied just before buds begin to break in the spring. Call the Helpline to receive a copy of this leaflet.
POSTED 3/2/04
Cocoa Mulch may hurt dogs-- In the recent Long Island Horticulture News sent to their industry was an article about the potential for this popular mulch to harm dogs when eaten. Two toxic methylxanthines, specifically theobromine and caffeine, are found in this mulch (also in chocolate), often higher in the hulls after processing than before. Lethal dose (LD50) for these is 100-200mg/kg of body weight. Seizures can occur as low as only 60mg/kg though, and at 20mg/kg may occur vomiting, diarrhea, bloating, and restlessness. So use such mulch with caution, or avoid it, if you have dogs or those wandering in your area. More details can be found at: www.aspca.org
Leonard P. Perry
Extension Professor, Univ. of Vermont
POSTED 3/15/04
Helpful article on common tree ailments:
Protect Your Trees from Winter Weather http://www.apsnet.org/media/press/WinterTrees.asp
POSTED 3/19/04
Vermont Vegetable and Berry Newsletters put out by Extension can be viewed online here:
http://www.uvm.edu/vtvegandberry/newsletter/datenavbar.htm
Lots of good tips and information. This and other helpful links can also be found on our Links page.
POSTED 3/31/04
EDIBLES FOR SHADE are mostly leafy, and can produce a decent harvest with five hours or less of direct sun per day. They can be used decoratively in the beds and borders. Parsley makes a great border, and so do colorful lettuces. A bright red stemmed Swiss chard was used at Longwood Gardens paired with a harmonizing red coleus. Other shade tolerant edibles include arugula, chervil, bee balm, cabbage, beet, borage, scallions, mint, chive, coriander, cress, escarole, kale, mustard, pansy, pea, sage, sorrel, spinach.
TUBEROUS BEGONIA BULBS that you saved from last year are best planted now, concave side up, in regular potting soil. If you haven't saved them from last year, it can easily be done next fall. Wait until the plant dies back, gently remove the stem, unpot and store the bulb in barely damp peat moss in a cool dark place for the winter.
MAPLE AND BIRCH TREES are pruned after they leaf out. Spring blooming shrubs are pruned after they bloom (forsythia, lilac). Summer blooming shrubs are pruned while dormant.
A FORSYTHIA shrub that has been neglected or overly pruned into a lollipop can be rejuvenated. It may look homely for a year or two, but will soon be back to its glorious self. First, cut all branches back to one foot tall. When new growth has grown to two feet tall, trim the tips to the first set of sideshoots to encourage branching. Also cut out any weak shoots. To maintain a mature forsythia, right after blooming, prune out all dead wood, and stems that are thicker than your thumb. Prune right down to the ground. Then remove to the ground no more than one third of branches crossed or inward-growing to the center. This will allow more light and ventilation to the center.
POSTED 5/5/04
LAWNS Homeowners have been finding numerous white grubs in the soil and asking for recommendations for treatment for this problem. Before treatment is begun, however, several steps should be followed:
All of the above information is capsulized from the following sources, which offer more specific information and make excellent reading:
Update information from UMass Turf Program includes the following two key points for pesticide control of white grubs:
IMIDACLOPRID, often sold as Merit(c), is slow acting but long lasting. It is not recommended for Spring application, based on trial results in Ohio, Pennsylvania, Massachusetts and other locations. In New England, Imidacloprid should be applied between late June and early August. It is then in the soil when the eggs hatch into grubs. For more on this update, see http://www.umassturf.org/mangement_updates/management_updates.html
Many pest problems on vegetables can be prevented by using a physical barrier, such as a polyester row cover, installed at the time of planting seeds. The cover keeps the adult insect from reaching the seedlings and laying it's eggs on or around them. Examples of these problems are: leaf miners in spinach, beets, Swiss chard; carrot pests (http://www.uvm.edu/extension/publications/el/el64.htm); worms in radish; flea beetles (http://www.uvm.edu/extension/publications/el/el71.htm). If you have the problems now, remove affected parts. Chemicals do not reach between leaf surfaces.
HYDRANGEA LEAF TIER shows up as wrinkled and tied together leaves at the growing tips of stems on hydrangea shrubs. Just pinch off those affected tips, the shrub will not be damaged, and will grow bushier.
SAWFLY LARVAE ON MUGO PINE, ROSES, and COLUMBINE: Seen as small worms with dark heads, massed on the ends of the plant. These larvae can be knocked off with a strong stream of water, needing several tries, so don't get discouraged. Birds love them. http://www.uvm.edu/extension/publications/el/el241.htm
BOTRYTIS on peony will appear as blackened leaves and stems. For this year, clip out and destroy infected areas. Clean tools with alcohol. Next Spring, apply a fungicide when the leaves are emerging from the ground. When buying products, be sure your plant and your problem are listed on the label. http://www.uvm.edu/extension/publications/gardendisease/gd32.htm
CABBAGE is often damaged by flea beetles, so plant radishes nearby to attract the flea beetles to their leaves. The radishes don't mind, and you get two good crops.
POSTED 5/17/04
TENT CATERPILLAR is common and has hatched for this spring. Cherry, apple, hawthorn, peach, plum, some deciduous shade trees, pear and roses may be attacked. Watch for the beginnings of a tent in the fork of the tree. Put on a glove and remove the web and small caterpillars by hand and crush them. Some people take a stick and tear open the web as often as necessary so the birds can get to the caterpillars. The caterpillars actually leave the web for feeding, and go back to it for resting.
Maintain ORGANIC MATTER content in the soil by adding compost, composted cow manure, peat moss, or green manures tilled in.
POLLINATION of vegetables can be improved by planting flowers to attract bees. A row of branching type sunflowers along the edge of the garden can be helpful.
FERTILIZERS high in ammonium content, such as fresh manure, can chemically lock up the calcium in the soil and make it unavailable for the plants. See the GD 01Blossom End Rot leaflet for more information.
Grass seed germinates at a soil temperature of about 55 degrees F. Get your pre-emergent for crab grass applied before the seeds germinate.
Spread the word as well as the fertilizer. Green Mountain Fertilizer Company (GMF) has heard the pleas of all those with excessive phosphorous showing on their soil tests. They have formulated and are selling phosphorous free lawn fertilizer. So far have heard that Green Mountain Fertilizer is sold at Depot Home and Garden in Essex Junction and at LD Oliver Co. in Milton, their home base. Gardener's Supply has a P free fertilizer. Milorganite, which is another P free fertilizer, is a waste treatment plant by-product, is for use on the lawn only.
POSTED 5/24/04
Forest and Eastern Tent Caterpillars Increasing in Vermont
From: Barbara Burns, Vermont Agency of Natrual Resources
Forest tent caterpillars are becoming more noticeable this spring. Although the population seems to be increasing statewide, the most dramatic numbers have been observed in southern Vermont. Heavy damage has been observed in western Rutland County, where the last outbreak began over 25 years ago, and where isolated areas of defoliation were observed in 2003.
Defoliation of sugar maple and oak is already visible. Reports of large Numbers of caterpillars spinning down on webs, and masses of caterpillars observed on tree trunks, have been even more common. This caterpillar continues to feed well into June, so more defoliation is expected.
Pictures of forest tent caterpillar, and more information about the life cycle, are available at the following websites. (Although we consider forest tent caterpillar a major pest of sugar maple here in Vermont, in other parts of North America, it is considered a pest of aspen, tupelo, and other regionally important species.)
http://www.forestpests.org/vermont/forest_tent_caterpillar.html
http://www.na.fs.fed.us/spfo/pubs/fidls/ftc/tentcat.htm
Forest tent caterpillar can have a serious impact on tree health. The last outbreak peaked in 1982, with over 300,000 acres defoliated statewide. By 1984, sugar maple decline and mortality were noticeable on about 30,000 acres which had been defoliated.
Look for the larvae of forest tent caterpillar. These caterpillars are most noticeable when they spin down on threads to migrate or when they loiter in groups on the boles of host trees. They may form silken mats on the stems where they congregate but do not construct a web or tent as does the eastern tent caterpillar. In areas of defoliation, there will be chewed, tattered, or lacy leaves, a lot of sunlight is reaching the forest floor, particles of leaf on the ground, and brown caterpillar pellets collecting on the leaves of ground cover plants. You may hear the "pitter-patter" of the pellets raining down.
Healthy trees with significant damage will refoliate by mid-July. Refoliated leaves are small and light green or reddish in color, compared to darker undamaged leaves. If evidence of forest tent caterpillar is noticeable, this would be a bad time to do any thinning or other selective harvests. Reducing the basal area concentrates the same number of insects on fewer trees. It also piles another disturbance on trees which may be low on carbohydrates.
It's especially important to keep an eye out for forest tent caterpillar in sugarbushes, where defoliation may reduce sap production and have a greater impact on tree health. Sometimes, it's worthwhile to spray sugarbushes to prevent defoliation. Although it's too late to plan for spraying this year, stands with noticeable populations this spring can be revisited in late summer or fall for egg mass sampling. Where egg mass numbers are high, the organic insecticide, Bt, can be applied from the air next spring. A ballpark cost to the landowner has been $20-$30 per acre. This requires substantial advanced planning, since permit applications for aerial spraying are issued on a site-by-site basis.
In 2003, bruce spanworm was the more widespread sugar maple defoliator. This green inchworm is also around this spring. Because its defoliation occurs earlier, trees with the same amount of damage recover faster than they do from forest tent caterpillar.
The eastern tent caterpillar is also at very heavy levels this spring. Its nests have been widely observed in the crotches of cherry and apple trees. Unlike the blue forest tent caterpillar, the eastern tent is mostly black, with stripes down its back instead of white spots. The eastern tent caterpillar hatches earlier, and is nearing the end of its feeding period. Eastern tent caterpillar information can be found at:
http://www.forestpests.org/vermont/eastern_tent_caterpillar.html
http://www.fs.fed.us/na/morgantown/fhp/palerts/etc/etc.htm
POSTED 6/2/04
BACTERIAL AND FUNGAL DISEASES will be growing during the cool wet weather. Besides the specific information given in the leaflets noted below, be aware that diseases attack plants that are already stressed. There are cultural activities that can help trees and shrubs stay healthy, and thereby reduce the damage from diseases.
1. Keep all trees and shrubs healthy. Enhance the soil in their root zones once in the spring with a balanced fertilizer, such as 5-10-10 or 10-10-10. If you are in an area with high phosphorous content in the soil, choose a fertilizer with a low or no phosphorous component. That would read as 5-0-10 or 10-0-10.
2. Keep trees and shrubs watered during a drought, if possible. Newly planted trees and shrubs should be watered to equal 1 inch per week of water if no rainfall occurs.
3. Use mulch sparingly around trees and shrubs to conserve moisture and keep weeds and mowing equipment away. Use only 3inches or less of mulch, and never against the trunk or stem. Covering the insides of the bases of shrubs leads to diseases and death of the stems.
4. Use clean tools when pruning, sterilizing if possible between cuts with a 10%bleach solution or rubbing alcohol.
5. Clean up diseased plant material, especially in the fall. Do not put diseased material in a home compost pile unless it will be heating up properly.
6. Install disease resistant varieties in your landscape when possible.
7. Pledge to monitor your property frequently, coffee or tea cup in hand, to discover disease or pest problems early. That way you can go back and treat the problems more easily with less expense and less toxic products. Timing is crucial, so begin your scouting walks even before the leaves pop out.
FIRE BLIGHT (http://www.uvm.edu/extension/publications/gardendisease/gd15.htm) You will recognize this by seeing dead terminal shoots, the tender new ones, drooping and blackened as though by being scorched. To control, prune out diseased shoots and nearby cankers, as described on the leaflet. A spray program may be needed next spring before leaves emerge. See leaflet.
BOTRYTIS (http://www.uvm.edu/extension/publications/gardendisease/gd32.htm) is a fungal blight that thrives in cool moist conditions. See entry below of 5/5/04 for more information if you are dealing with this disease.
ANTHRACNOSE (http://www.uvm.edu/extension/publications/gardendisease/gd2.htm) is a fungal disease common on maple trees, but also may be found on oak, ash, sycamore and elm trees. It is prevalent during a cool wet spring. For more information, see the leaflet.
LILACS and other spring blooming shrubs are ready for pruning now. Removing the old blooms helps the shrubs by keeping them from using energy to form seeds. Fertilize now with a balanced fertilizer. Mulch lightly if at all. Mulch does not prevent lilac sucker shoots from coming up, but it may prevent rain from reaching the root zone if it is more than 3 inches deep.
LAWNS
We have a brand new leaflet, written by Sid Bosworth, Extension Agronomist, Plant and Soil Science Department, Univ. of Vermont, that outlines "Low P, No P and 'Lake Friendly' Fertilization Programs for Lawns". It also lists ways of "Reducing the Risk of Excessive Nitrogen Fertilization on Turf". This leaflet is available by calling the M.G. Helpline at 1-800 639-2230 or 656-5421 and requesting a copy be sent.
Here is a website to visit if you are thinking about using nematodes for grub control in your lawns. The main thing with nematodes is the timing - they don't last more than a few weeks so you want to put them out when the grubs hatch in late summer, not in the spring. http://www.oardc.ohio-state.edu/nematodes/
TWO NEW BROCHURES FROM THE VERMONT DEPARTMENT OF AGRICULTURE
EMERALD ASH BORER is the name of a new exotic beetle from Asia that is devastating ash trees in the U.S. The adult is a slender metallic green beetle that can be seen between mid-May and late July. The evidence of the larva shows as dead branches on ash trees. The Vermont Department of Agriculture has published and has available a brochure to help with location and identification of this pest. Click Here for the brochure and visit http://www.vermontagriculture.com/CAPS/invasive/forestpests/eab.htm for more information.
Call them at (802) 828-1246 if you see ash trees dying.
GIANT HOGWEED is a huge weed that can inflict a serious rash if contacted with bare skin. It is growing out of control in many areas of Vermont. The Vermont Department of Agriculture has published and has available a brochure to help with location and identification of this pest. Click Here for the brochure and visit http://www.vermontagriculture.com/CAPS/invasive/otherpests/gh.htm for more information.
To report a stand of Giant Hogweed, or to request help with identification or eradication, contact the Vermont Department of Agriculture at (802) 828-1246 during business hours.
POSTED 6/18/04
Below is a press release describing severe damage to cedar, which is very evident from the Interstate south of Barre. You may find this pest attacking your cedars also, be on the look out for it.
Severe Browning of Cedars in North-Central Vermont primarily due to a tiny Leaf-Mining Insect
Waterbury, VT-Forest health specialists from the Vermont Department of Forests, Parks and Recreation report that a heavy infestation of a tiny insect called the Arborvitae Leaf Miner has led to severe browning of northern white cedar in north-central Vermont.
The damage is especially noticeable in the Williamstown-Berlin area adjacent to I-89 and along Route 63, the South Barre access road where there is a large concentration of northern white cedar, the single host for this insect. Damage was also noticeable in the spring of 2003 but has dramatically increased this year due to a large increase in insect populations last year. The brownest trees have the most leaf mining due to the insect. Some lighter damage is noticeable elsewhere in northern Vermont.
Trees look browner from a distance than up close, with clusters of brown seeds in the tops of trees contributing to this appearance. A closer examination reveals green shoots beginning to emerge behind the dead tips so trees should look better in a few weeks.
The insect hollows out portions of the leaves and causes the foliage beyond this point to turn yellow and die. Recent stress from drought in 2001-2002, followed by two very cold winters, has made trees less able to withstand the insect damage and appears to have increased the amount of foliage dieback associated with the insect injury. The tiny tan moths should begin emerging in mid-June to lay eggs for next year but usually, parasites and other natural factors end up reducing population levels.
Some trees have very little live crown left and are likely to die but most should recover. Northern white cedar can usually survive after losing as much as 80 percent of its foliage.
POSTED 6/21/04
Viburnum Leaf Beetles: Several of you have commented on the heavy defoliation of your Viburnum bushes, this includes the highbush cranberry which is widely planted throughout Burlington. Be prepared, the larvae will go into the soil soon to pupate and then emerge as adults in July. The best management is to prune off branches with eggs from October until early May. Click here for the most current information from Cornell's Citizen Program (Adobe Acrobat document).
You can obtain additional information from these websites:
http://www.hort.cornell.edu/vlb/index.html
http://www.entomology.cornell.edu/Extension/DiagnosticLab/IDLFS/VLBfactsheet2003.html
POSTED 6/24/04
The beginning of summer also signals the beginning of the West Nile virus season. As an effort to better protect Vermont citizens and our communities, the Vermont Department of Health has increased the level of public education about West Nile virus for this season. More specifically, we are targeting local gardening groups and other outdoor enthusiasts.
West Nile virus first appeared in the United States in 1999, when at least 62 people in the New York City area got sick and seven people died. Since that time, the virus has spread throughout the United States. The following information from the Vermont Department of Health discusses commonly asked questions about West Nile virus. Click here for the this information in the form of fact sheets (Adobe Acrobat document)
How do people get West Nile virus?
The vast majority of infections are from the bite of an infected mosquito. Mosquitoes are infected when they feed on an infected bird. When an infected mosquito bites a person, the virus is injected into the person and may cause illness. West Nile virus can also be spread by organ transplantation, blood transfusion, from a mother to fetus, and possibly by breast milk.
Can people get West Nile virus from birds?
There is no evidence that a person can get the virus from handling live or dead birds. However, wear gloves whenever handling a dead animal, including birds.
If a mosquito bites me, will I get sick?
Most mosquitoes are NOT infected with West Nile virus. Even if an infected mosquito bites you, your chances of getting sick are low. Most people who are infected do not have any symptoms. About 20 percent of people who are infected have a mild illness and recover with no treatment. Less than 1 percent of people who are infected develop severe illness, like encephalitis or meningitis.
What are the symptoms of West Nile virus infection?
Most cases are mild. Symptoms may include fever, headache, body aches, skin rash, and swollen lymph glands. More severe cases can cause headache, high fever, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, paralysis, and rarely, death.
Who is at greatest risk of becoming ill from West Nile virus?
People over age 50 have the highest risk of getting severely ill if bitten by a mosquito infected with West Nile virus.
How is West Nile virus infection treated?
There is no specific treatment for West Nile virus, but the symptoms can be treated. In severe cases, hospitalization and treatment in an intensive care unit may be required.
How common is West Nile virus in Vermont?
West Nile virus has been detected in dead birds, mosquitos, and horses. There was one documented case of human illness caused by West Nile virus in Vermont in 2002.
What can I do to protect myself from West Nile virus?
You can take steps to reduce mosquito breeding areas near your home and prevent mosquito bites.
What can I do to keep mosquitoes from biting?
What can I do to reduce the number of mosquitoes around my home?
Mosquitoes need water to reproduce. They can breed in any puddle or standing water that lasts more than four days. By removing areas of standing water around your house, you will eliminate their breeding grounds and reduce the number of mosquitoes.
Additional information about West Nile can be accessed at:
POSTED 7/13/04
WATERING THE LAWN AND GARDEN is best done by 10am with ¾” to 1” water, once or twice a week. Light watering in the evening is the worst way to water. It leads to shallow root systems that are close to the surface and so will dry out readily. Once the fine root hairs dry out, they die and the plant has to take the time and energy to make new ones before it can take up water again. It also leads to mildew problems from wetness of the leaves all night. It also leads to happy grubs congregating in shallow moist soil, leading to hungry skunks ripping everything up to get to the grubs.
CABBAGEWORMS (EL63) on broccoli, cauliflower, and cabbage can be controlled with a Bacillus Thuringiensis spray. Spray the leaves, top and undersides, not the larvae. The larvae have to ingest some of the Bt, as it works as a stomach poison.
MAPLE GALL MITES (EL6) are causing the swellings and growths on maple leaves. These may be unsightly, but rarely warrant treatment with a spray. The leaves are still able to carry out their job of manufacturing chlorophyll.
RASPBERRY CANE BORER (EL13) adults oviposited eggs in the long, succulent first year canes in late June and early July, and now those canes show the characteristic “wilted crook” of the tips above the two parallel rows of punctures. Prune the wilted cane tip 2”-3” below the lower row of punctures and destroy it.
SQUASH BUGS (EL83) are big gray bugs at the base of the plants. Push them into soapy water, or use a spray of Sevin or Malathion.
SQUASH VINE BORER (EL84) may be the culprit if your squash vines show daytime wilting and stunted growth, even if well watered. Check the stem near its base for a hole. Slit the stem lengthwise there and remove the larva, then bury the damaged stem with moist soil so it can grow new roots. Prevention is the best treatment. Plant early varieties that will be big enough to withstand the borer larvae. Wrap the stem with an old nylon stocking that stretches as the stem grows. Or wrap with crushed aluminum foil. Hill the soil around the stem so egg laying is discouraged. Apply a row cover at planting time, forming a physical barrier against any insect flying in to lay eggs or chew on your plants. A row cover may need to be removed for pollination by bees, or just do the pollinating yourself by removing a male blossom and rubbing the pollen on the stigma of the female blossom(s).
STRIPED CUCUMBER BEETLES (EL68) are on cucumbers. Handpick into soapy water or spray with a pesticide.
VIRUSES ON RASPBERRY include leaf curl and mosaic. They cause the leaves to turn various shades of green and light yellowish green, along with a declining yield. Aphids from any wild brambles in the neighborhood carry these viruses, so remove all bramble within 200 yards of your plants. Any infected plants should be removed and sent to the landfill, and the soil not used for raspberries for 5 years hence. Also, it pays to always purchase certified virus-free plants.
ZUCCHINI and other members of the cucurbit family may become victims of the CHOPANOPHORA WET ROT, a fungus that causes young squash to blacken from the tip back. The tip will appear shrunken and black. Hot, wet weather encourages fungal activity, as does poor air circulation in a crowded garden. The best cure is prevention. Provide adequate space for each plant, using trellises if needed. Make sure your soil is well drained. Dispose of infected fruits properly, meaning out into the landfill. Use fungicides if the infection gets too severe.
POSTED 7/20/04
IMIDACLOPRID GRUB TREATMENT products should be spread on lawns in July and early August for effective treatment of white grubs in lawns. The adults are beginning to fly and mate, and then lay eggs in the soil. The larvae will hatch from the eggs in August, and the pesticide will be able to destroy them while they are small. Follow all package directions for usage.
CLUSTER FLIES, LADYBUGS. AND BOXELDER BUGS that come indoors for the winter can be prevented somewhat by spending some time this summer tightening up your home. Michael F. Potter, a University of Kentucky Entomologist, suggests the following:
1.Install doorsweeps at all exterior doors. Gaps of 1/16 or less allows entry of bugs and spiders. A gap of ¼ inch allows entry of mice. Pay attention to the bottom corners, especially. Caulk the sills of door thresholds. Garage doors should have a rubber seal; it remains more flexible than vinyl in cold weather. Sliding glass doors can be sealed by lining the bottom track with 1/2 to ¾ inch foam weather-stripping.
2.Seal utility openings where pipes and wires enter the foundation and siding. These are common entry places for insects and rodents. You can use caulk, urethane expandable foam, steel wool, copper mesh, or other appropriate sealant.
3.Caulk cracks around windows, doors, fascia, etc. using a good quality latex caulk.
4.Repair gaps and tears in screens in windows and doors.
5.Install ¼ inch wire mesh (hardware cloth) over attic, roof, and crawl space vents to keep out rodents.
6.Consider supplementing your efforts with an exterior treatment with a pesticide. This is not as permanent as all of the other mentioned activities, however.
POSTED 7/27/04
Wild parsnip is in bloom across VT right now. It is invasive and also may cause phytophotic reactions; blistering and burning of skin. Here are 2 links with info that may help you avoid this weed and it's burn potential.
POSTED 7/28/04
VACATION GARDENS are gardens you leave behind when you go away for vacation. A few things need to be done before you leave:
TOMATO DISEASES are getting a boost from wet weather:
AUGUST PLANTINGS can extend your harvest year. Early in August, start sowing seeds of escarole, leaf and head lettuces. Later sowings could include leaf lettuces, spinach, Swiss chard, beets, turnips for greens, kale, mustard greens, radishes, chervil, dill and Oriental greens. If transplants of broccoli and cauliflower are available, you may get a crop by Halloween.
FALL WEBWORM damage can be kept to a minimum by scouting and early detection and treatment. When a few webs around the terminal branches become noticeable, prune out the infested parts and plunge them into soapy water. Or spray the foliage (not the worms) with bacillus thuringiensis, a biological control. Follow label directions. See leaflet EL 145.
POSTED 8/23/04
FERTILIZE LAWNS after August 20. If you fertilize only once a year, late August and all of September is the time to do it. The grass will be slowing down with top growth and making more and deeper roots in the cooler weather. August 20 to October 20 is also the best time to reseed lawns. The soil is cooling down, the weed seeds are less likely to germinate, and the rains will help with the watering of newly germinated seeds, which have to be kept moist for a month or more. Remember, when you plant a mix of grass seeds, the varieties do not all germinate at the same time, so keep watering. But do not keep the ground heavily soaked for that month or more. Then you can get fungus problems, especially if the general weather remains humid.
“LOW MOW” OR “NO MOW” LAWNS may be your answer to lawn difficulties. Even the English are moving toward them. These lawns are seeded with a mixture of fine fescues, which tolerate dry, infertile, acidic (pH 5.5-6.5) conditions, but need to be grown in a region that receives at least 20 inches of annual rains. The Northeastern U.S. and southern Canada are such regions. The mixture should include creeping red fescue (Festuca rubra), chewing fescue (F.r.var.communata), sheep fescue (F. ovina), and hard fescue (F.o.var.duriuscula). Fescues are slow-growers, needing less mowing, have fine leaves and so are not recommended for heavy traffic areas. They tolerate the conditions mentioned above, in shade or sun, but will not tolerate wet, poorly drained soils. Some annual rye in the mixture will germinate more rapidly than the fescues, serving as a ‘nursery’ for the germinating fescues.
BUTTERFLY WEED is sometimes used as a cut flower. This, a member of the milkweed family, and other euphorbias have a milky sap that is injurious to the eyes. Therefore, always wear goggles when handling the cut stems and leaves, even a long time after they have been cut.
STRAWBERRIES need to be watered well in mid to late summer, because that is when the cell size of the spring fruit bud is determined. Also, putting floating row covers on the beds through the winter will enable the plants to be stronger and yield more fruit next season. Organic strawberry growing for the home gardener should include raised bed rotation, compost in the soil, organic mulch and drip irrigation.
POSTED 10/26/04
IF THE RAINS HAVE BECOME SCARCE IN YOUR AREA THIS FALL, REMEMBER TO WATER TREES AND SHRUBS TO MAINTAIN AT LEAST AN INCH A WEEK RIGHT UP UNTIL THE GROUND FREEZES.
VOLES AND MICE need nesting sites for the winter. Early mulching of perennial beds provides cozy conditions for them amongst your plants, so wait until the ground is frozen and then mulch. For now, if you are inclined to use them, set out mousetraps baited with peanut butter or apple. Perennial beds close to the house seem to be especially preferred by rodents. Trees and shrubs that are already mulched need to have the mulch pulled away from the stems.
Helpful information is available for winterizing your yard and garden. Check out the following leaflets:
OH 3 “PREPARING THE GARDEN FOR WINTER” has tips for cleanup, proper mulching, storing summer bulbs, protecting trees, shrubs and perennials. Sometimes forgotten in the process of cleaning up is the need to treat tools, tomato cages, reusable plastic, stakes, trellises, wire, markers, pots, flats and anything else you can think of with a solution of one part bleach to 9 parts water to deter spreading of diseases to the next year’s garden. http://www.uvm.edu/extension/publications/oh/oh3.htm
OH 4 “WINTER PROTECTION OF ROSES” includes instructions for various methods of covering roses for the winter. Heed the cautions that winter protection is best applied in late November, so that the roses can develop some of their own winter hardiness. http://www.uvm.edu/extension/publications/oh/oh4.htm
FR 20 “PREPARING YOUR FRUIT TREES FOR WINTER” tells how to prepare the orchard floor so as to deter mice and voles, install mouseguards around trees, repel deer and more. Call the Helpline at 1-800-639-2230 for a copy.
GD 20 “WINTER INJURY” discusses six types of winter injury to plants. http://www.uvm.edu/extension/publications/gardendisease/gd20.htm
EL 38 “HOUSEPLANT PESTS” will help you find, identify and deal with chewing and/or sucking insects on your indoor plants this winter. http://www.uvm.edu/extension/publications/el/el38.htm
OH 17 “HOUSEPLANT PROBLEMS” provides an amazing chart of symptoms and causes to help you diagnose what ails your indoor plants. http://www.uvm.edu/extension/publications/oh/oh17.htm
Contact Vermont Master Gardener at master.gardener@uvm.edu.
Contact webmaster sarah.kingsley@uvm.edu with questions or comments about this web site.
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