Dr. Dean Krauskopf
“The Gardening Show”
The Gardening Show
The abnormally dry areas in Michigan are expanding.
Lacewing populations increasing – a very good thing.
White pine weevils damaging many conifers and scouting for gypsy moth egg masses.
Check your veggies as well as ornamentals for thrips and twospotted spider mites.
Great Lakes IPM is a good source for pheromones and other IPM materials.
Wheel bugs – important predators.
Carol in Sterling Heights had removed the lower branches of her spruce due to what I think was spruce decline and wondered about adding coil underneath the tree. Here’s information from Texas A and M.
Jim in New Vienna Ohio wondered about the difference between potting soil and potting media.
Jeff in Port Huron wondered about using the waste of water from his koi pond on his flowers and vegetables. I don’t see a problem unless you’re using a algaecide containing copper ir a quaternary ammonium compound which over a period of time can harm plants. There could be a concern splashing water containing fecal material on leafy greens in the garden. I would avoid using the water on such crops and carefully wash all produce before eating.
Jerry in Saline described the symptoms of blossom end rot in his tomatoes. Here’s how to reduce the incidence of the problem.
John in St. Clair Shores wanted information on broad mite control on cannabis.
Releaf Michigan Executive Director Melinda Jones talked about her organization and the Big Tree Hunt.
The Sunset Garden Celebration at MSU’s Tollgate Farm, Saturday, July 21, 4-7 pm is a great opportunity to pack a picnic and enjoy beautiful gardens, music, education and vendors. Free but no alcohol or pets.
One of the keys to a healthy lawn is mowing at the correct height.
Milkweed bugs have appeared.
Twospotted spider mite can cause leaf drop and branch death for many plants but Dwarf Alberta Spruce, pyracantha, and burning bush a very susceptible. The article suggests using spray oil to control these pests but make sure you use Ultra Redefined Spray oil or one of the organic oils and don’t spray when the plants are stressed or it’s above 70 degrees. Another approach is to direct a high-pressure water spray to the underside of the needles or leaves about once a week. This will physically blow off mites from the leaves and the high humidity reduces egg survival.
You should be able to hear the cicada song soon – along with cicada killer wasps.
Watch out for magnolia scale.
Is my tree infested with ghosts? Southern Masked Chafers adults starting to fly.
Edward from Shelby Township wondered the best way to trim a Blue Spruce and when to do it. Usually we don’t prune spruce except to remove broken branches or branches killed by Cytospora canker which is best done in winter. Another cause of branch death is spruce decline which is complex of diseases. To shape young trees part of the expanding shoots (called candles) can be removed in the spring.
Randy in Port Sanilac just put in a new lawn and was wondering how often to water and when to mow for the first time. Here’s more information.
Walter in Southgate is fighting either the cultivated morning glory or “wild” morning glory which is better named field bindweed. The plants are very similar, but morning glory stems and leaves are larger, and the flowers are blue or purple. Field bindweed leaves are about 2 inches across, the flowers are white, and the stems are very small, almost like threads. Since Walter said the flowers were purple, it’s more likely morning glory. Both plants are extremely difficult when growing among the other plants. Follow the directions in the material on field bindweed for control of both plants.
Square Foot Gardening Day was July 1, Mel Bartholomew developed the square foot gardening technique which has transformed many gardens.
I haven’t ordered this, but it looks interesting Pop Chart Labs American Blooms Poster $29.00. MSU Pollinator Champions On-Line course is self-paced and free. There is a small fee to become a Pollinator Champion.
Spotted wing Drosophila increasing.
Turf care tips for golf courses may also apply to intensely managed home lawns.
Many lawns are beginning to go dormant. Here’s is information on how to maintain your grass during this time.
Sunflower Head Clipping beetle attacking a range of plants.
There is an American Lotus.
More information on Entomophaga maimaiga control of gypsy moth.
Bob in Rose City‘s hollyhocks were being attacked by what sounded like Hollyhock Weevil but could also be sawflies of Japanese beetles. Rust can also be a problem.
Jim in New Vienna, Ohio wondered how to protect his potted rose tree during winter. I suggested he put it in an unheated or very cool area in his house after the leaves dropped in the fall. Here are techniques for protecting roses planted in the ground.
Kevin from Rochester Hills wondered if it was possible to grow a California Coastal Redwood or Giant Sequoia. The California Coastal Redwood has very specific growth requirements that restrict its range to within 50 miles of the Pacific Coast and I don’t think we could meet these needs in Michigan. The Giant Sequoia is hardy to zones 6-8 so the Metro Detroit area is at the lower end of its low temperature tolerance, but it should be OK in a protected micro environment. The largest Giant Sequoia in Michigan is located in Manistee. The Dawn Redwood does well in Michigan.
Mary Anne in Waterford’s condo association wants to replace trees on their property. They have developed a list of criteria for the new plants including disease and insect resistance, spring and fall color, screening etc. These are the steps I would suggest for selecting the plants.
1. Perhaps the most important is to learn from what happened to trees that were lost or damaged. What is the soil type, how rapidly does water drain away, exposure to winter winds, irrigation, etc. This will determine the limitations of each area.
2. Avoid overusing one genus or species. We planted a blue spruce for years because of its beauty. However, our climate has become hotter and dryer which has stressed the trees and a disease complex has evolved that is killing them throughout the area. This is an opportunity to enjoy the extremely wide range of plant material available and avoid another massive loss. There is a wide range of information on the internet. Reference 1. Reference 2. Reference 3. Reference 4. I also like Eastern Trees, Perterson Field Guides; National Audubon Society Field Guide to North American Trees; Trees of Michigan, Lone Pine Press; and Manual of Woody Landscape Plants, Dirr.
3. Remember there is no perfect tree for each site, weigh the pluses and minuses carefully.
4. Patience can save you a lot of money. Smaller transplants will usually catch up to larger, more expensive specimens within three to five years.
5. Work with a professional. There are many fine nurseries in the Oakland, Genessee County area. Size of the nursery doesn’t determine the expertise of their people. Ask for references, visit sites they have designed/installed and enjoy the process.
6. Determine a three-five-year planting plan to ensure that you new trees aren’t damaged by an unusually hot, dry bummer or cold winter.
Kim Parr Director of the Crocker House Museum, 15 Union Street, Mount Clemens, was my guest talking about the Crocker House Garden Walk and Breakfast Saturday, June 30. Twelve gardens will be on the tour this year. For more information and to purchase tickets call 586-465-2488.
I saw the first lightning bug this week. Here’s a wonderful picture of lightning bugs in Southern Michigan.
Stems of Mike in Novi‘s roses are dying. The most common cause is Rose Canker.
Deborah in Detroit wanted to find Four O’Clock flower seed. Seed should still be available in garden centers and even grocery and big box stores. Here’s more information.
Let’s all take a deep breath and read this very good article on Brown Recluse Spiders by MSU’s Howard Russell.
Giant hogweed, while dangerous, is very rare in Michigan. Here’s more information.
Bob Tritten, MSU Regional Fruit Educators found the first Japanese beetle of the season.
Imported Rose Sawfly is attacking my roses.
More on gypsy moth.
Dodder is a parasitic plant that is very hard to control.
More on lace bugs.
Renee from Royal Oak is fighting bishop’s weed. While it is satisfying to cut it off and treat with herbicides, this won’t control the rhizomes which sprout back. Since the most effective herbicides enter through the leaves (not the stems) and translocate down to the rhizomes in the fall, I suggest cutting the vines back until August and then let them grow to provide plenty of leaf surface. Apply a herbicide containing either glyphosate or triclopyr to the leaves beginning in mid-September\, then again at the end of the month and then two weeks later. You won’t see much damage this fall but next spring you’ll see how effective it was. If the plant has spread to neighboring yards thi should be a group effort or it will just move back and forth between yards.
Tracy from Ypsilanti wonders how and when to prune her Japanese maple.
Jimmy from China Township thought lichens were killing his spruce limbs, but more likely Cytosora canker or spruce decline is attacking the tree and allowing you to see the lichens. Samples should be submitted to MSU for positive identification.
An easy way to tell when to water hanging baskets and pots is to lift them; water when they feel lighter than right after watering. If you have ceramic or clay pots, tap the side, if it rings it’s time to water.
When planting media dries, it shrinks. If you water only once, a lot of the water will run off around the edge and not wet the media. Water and then wait 10 minutes or so for the media to swell and then water again.
June apple drop is occuring which is a natural process where the tree balances the amount of leaf surface against the number of fruit.
The conditions are right for Powdery Mildew.
Peach leaf curl can be a real problem.
I’m seeing a lot of browning turf especially on slopes. This is due to water stress where water has run off rather than soaking in and mowing too close.
The leaves of your hawthorn (Crataegus spp.), serviceberry (Amelanchier spp.), Cotoneaster spp. and firethorn, (Pyracantha coccinea) looking weird? Could be Hawthorn lace bug damage.
Bagworms may become a problem.
Scarlet oak sawfly feeds on a wide range of oaks.
Birds nesting in your mulch or is it the Birds-Nest Fungus?
Leaf-fold galls on oaks and black locust.
Fall webworm showing up.
Willow sawfly, Imported willow leaf beetle and Willow leaf gall mite.
Jerry in Livonia is fighting ground ivy.
Mary Anne also asked about the best time to water her lawn. Usually the only criterion is the turf must be dry before dark. I suggested 4 am because of the stable water pressure but you need to put out containers to make sure the system is working unless you enjoy getting up that early. From a physiological viewpoint, the best time to water is during the hottest part of the day, 11am-2pm to cool the turf, however for a healthy lawn this isn’t a big deal.
Brian in Troy‘s azaleas were infested with what sounded like azalea bark scale. Because control varies with the type of scale, MSU Diagnostic Services should be contacted about submitting photos/and or samples.
June 18-24 is National Pollinator week. Bee Palooza will be held Sunday, June 24, 1-4 pm at the MSU Horticulture Gardens. Also visit the MSU Bug House. Biology on Tap will be at 7:30 at The Loft in Lansing on June 20. You must be over 21 for this one though.
Want to learn about integrated pest management or update your skills? MSU is offering the Integrated Pest Management Academy online and at a very reasonable cost.
Cedar apple rust is showing up on cedars and apples.
Michigan strawberries are ripening! Here’s this years U-Pick Guide.
Canada thistle turning white? I love it.
A new non-native invasive pest, Spotted Laternfly.
You are the expert on what’s going on in your yard. If you see something strange report it to the Midwest Invasive Species Information Network.
Susan in Detroit was trying to get ride of Tree of Heaven. Cutting the stems encourages sucker formation which favors the plant. Herbicide applications in September-October will help. Note: the article suggests beginning applications in August. I suggest mid-September since the trees are in the city and won’t begin translocating the material into the roots until later than trees in less urban locations.
Richard in Sterling Heights was trying to identify the grass invading his lawn. This site from North Carolina State is very easy to use. Once the problem is identified go here for control information.
Wayne in Garden City cut down a mulberry growing between two fences, but shoots keep coming back. Applications of glyphosate or triclopyr containing herbicides during the summer will burn the shoots back, but to get control allow the shoots to grow during August and then apply the herbicide mid-September, early and late October.
Marie Osborne of WJR‘s news department lost her son John to an undiagnosed heart condition. John was the Pit Master at Slow’s Bar BQ and cooked for many other venues in Detroit. The Osborne family has established an endowment at Schoolcraft College to help culinary students continue their studies. Slow’s has added the “Plaid Pig” sandwich to their menu in John‘s memory to support the endowment. If you are unable to go to Slow’s, please join me in donating to the cause.
The leaves of Paul from Monroe‘s maples are turning black, curling up and falling off. The trees have a history of black spots on the leaves. I think his maples are being attacked by maple anthracnose fungus. The reoccuring black spots are most likely Maple Tar Spot. Neither issue is a threat to an otherwise healthy tree. Here’s more information.
The recent heavy rains and high winds are ideal for the spread of Fire Blight bacteria.
Spittlebugs are appearing on a wide range of plants.
Colorado Potato Beetle is not only a pest of potatoes but will also munch on eggplant and pepper.
Row covers are an excellent way to prevent insect damage.
I haven’t seen any Four-lined plant bug yet, but they will soon appear.
Lady Beetle larvae feeding on magnolia scale.
Keep an eye out for Calico Scale crawlers.
KnockOut Roses were introduced in 2000 as a low maintenance, sustainable rose. Now there is a group, American Rose Trials for Sustainability, trialing many other roses for low input and sustainability.
When peat-based media dry severely, they are difficult to rewet. Here’s more information. While the article mentions comercial wetting agents, I have found that just enough hand dishwashing soap for a little suds added to a gallon of water works well. Only apply once.
Linda from Grosse Pointe needs to enlist her neighbors in her battle against Creeping Charlie.
Toni from New Boston was concerned about an oak tree over her gazebo that seems to be leaning a little. Contacting a certified arborist is the best approach. No pruning should be considered until after a killing frost because of the risk of oak wilt.
MSU Tollgate Garden Volunteers Spring Plant Sale, 9 am – 2 pm, Saturday June 2nd. Meadowbrook and 12 Mile Roads.
Living Local – Next Seasonal Favorite, Monday June 4th 6 pm-8 pm. Sponsored by Jackson County Agriculture Council, Grand River Brewery and MSU Extension. Cooking demos highlighting local ingredients, suggestions for pairing with select beers and vote for your favorite dish which will be featured on the menu.
Here’s more on Eastern Tent Caterpillar.
Check your gardens for volunteer potatoes and help reduce the spread of late blight.
Some help with keeping your lawn healthy from Dr. Kevin Frank.
Temperature not the calendar determines when to plant.
Oak “apples” easy to see but cause little harm.
Pachysandra dying out? Could be Volutella.
A common invasive plant, Autumn Olive.
Spring wildflowers – a great reason to go walking in your back yard or nearby park.
The University of Michigan’s Nichols Arboretum has the largest collection of herbaceous peonies in North America and they are starting to bloom.
Fred in Indiana asked about what to plant near his door that would attract hummingbirds but not bees which started a lively conversation. Scott from Lapeer who is a bee keeper stated that red flowers are not attractive to bees as other colors. He also pointed out that MSU has lists of plants attractive for pollinators that if planted away from the door would be more attractive to bees than other flowers. Judy in Franklin has noticed bees working on Major Wheeler honeysuckle and someone suggested red cannas. Bev in Vermillion Ohio probably had the best suggestion. Don’t plant flowers near your door or patio and use feeders to attract hummingbirds. Note: I’ve seen bees feeding on hummingbird feeders but only when other sources of nectar aren’t available.
John in Clinton Township wondered about using pendimethalin, a preemergence herbicide, in his garden. Pendimethalin has a label for use in gardens and works well around transplants but will prevent vegetable seeds from germination. For more information go to the company’s website.
Jason in Taylor has been controlling weeds in his large garden using tillage and mulch but wondered about using glyphosate or other herbicides. I suggested using these materials only in the fall after the vegetables are harvested to remove weeds for the next spring. If there are large areas of weeds that have to controlled during the season, materials that burn down the tops of the plants such as Bonides BurnOut would help. Note Bonide is a long-time sponsor of the Gardening Show and there are products from other companies that would also be effective.
Don’t be tempted to lower mower height to keep up with grass growth. You will stress the plant and encourage weed growth.
Crabapples at the Secrist arboretum.
Rainy, cool weather is ideal for apple scab attack.
Cabbageworm moths are laying eggs on cabbage and other crucifers.
Boxwood leafminer can cause serious damage
Watch out for “Frass toothpicks” on newly planted or stressed trees. They are indicators of Ambrosia beetle attack.
Oystershell scale eggs are hatching soon so get ready to apply control measures.
Tips for reducing mosquito attack.
Ken in Livonia wondered how long it would take for his MacIntosh apple that he grew from seed to fruit. Since a seed propagated plant has new genetics, it’s hard to predict but he might get the next great apple variety.
Pete in Dearborn wasn’t having any luck growing poppies. Sounded to me like too little light or too much water.
David in Fenton wanted to remove ground cover that was moving into other beds. I suggested using a “burn down” material such as Bonide’s BurnOut periodically during the summer to weaken the plants and then either a material containing glyphosate or triclopry beginning in mid-September and then again in early October to kill the roots.
William in Washington has an ant problem in his lawn. Ants are usually not a lawn problem unless the grass has thinned out because of salt damage or other factors. In this case thickening the grass by proper watering and fertilization will correct the problem. The major exception is the mound ant so submitting a sample to MSU is the first step in control.
Toledo’s Flower Day Weekend is May 26-28 at the downtown Farmer’s Market.
Moving frequency and height has a great effect on your lawn’s health.
Forsythia had a hard winter, but the Eastern redbud is in full glory.
Rainy, cool weather is ideal for apple scab attack.
The Ohio State University Secrest Arboretum in Wooster, Ohio has one of the largest collection of crabapple varieties in the US.
The 51st Flower Day at the Detroit Eastern Market is Sunday, May 20.
Last summer’s drought may have caused winter injury on a wide range of plants according to Dr. Bert Cregg.
Check for Weir’s cushion rust on your blue spruce.
Black cutworm starting to show up in many young sweet corn and tomato transplants.
Roses too had a hard winter..
Don’t park under a tree infested with calico scale. .
Boxwood snap, crackle and pop. Could be boxwood leafminers.
Jon in Taylor needs to move a climbing rose and daylily. The easiest way is to use a spade to cut down 8 inches around the plant as far away from the stem as possible (watch the weight of the root ball). Then start digging across from one side, so you are under cutting the root system. As you cut across slide a sheet of 1/2 or 3/4 inch plywood underneath. As soon as the root ball is free, move the plant either to a temporary hole or a container if it will be replaced in the original hole within a few days.
Bill in Utica was finding large black ants in his home. These could be carpenter ants, which can cause significant damage. Since there are several types of ants that resemble Carpenter ants, the first step is to submit a sample to Macomb County MSU Extension or Diagnostic Services on campus have them identified.
Art in Newport put compost in his new beds. I suggested contacting MSU’s Soil and Plant Nutrient Laboratory to see if a compost of traditional soil test would be more appropriate for determining the nutrient status and pH of the compost.
Kenny was fighting weeds in his lawn. The first step is to identify the weed.
Elaine from Northville was wondering why her forsythia didn’t have many flowers. I think it’s related to the drought we’ve experienced for the last 3 summers and the up and down temperatures this winter. Pruning might also help. Dandelions were also a problem. A key way to thicken your lawn and reduce weed infestations is by fertilizing correctly.
Mary in Britton’s Eastern Redbud has cracks in the trunk.
Enjoy the flowers and then control dandelions.
Reduce the risk to pollinators when applying pesticides to fruit crops by following these guidelines from Dr. Rufus Issacs.
Elm Flea weevil damage will start showing up soon.
Find the average frost free date in your area on this table from the Michigan State Climatologist Office.
The bark on Anne from Allen Park‘s Japanese maple was being pulled off, probably by birds. The first thing to do is trim any loose fibers from the edges of the wounds and then apply something like Tanglefoot. Repellents that work by smell or taste aren’t effective on birds. Another approach would be to scare them off using rubber owls (the ones that move work best), rubber snakes or hanging old CDs from the branches.
Randy from Port Sanilac’s lawn was very bumpy. Part of the problem may be the type of grass. The first step is to positively identify the grasses and this key from NC State is easy to use. Another option may be topdressing the low areas.
Keith from Ann Arbor’s daisies and hostas were doing well but wondered if there was anything he should do this spring to increase the bloom time. Since the bed is next to a fertilized lawn area I suggested not fertilizing this spring and perhaps dividing them.
Mary from Dearborn’s dog was attracted to the rose fertilizer she used in the past. I suggested using common fertilizer such as 12-0-12 twice a year or a slow release fertilizer such as Osmocote or similar products every spring. You could also apply an organic that doesn’t contain blood meal such as Milorganite.
Daedre McGrath, Manager of the Trial Gardens at MSU’s Horticulture Demonstration Gardens was this week’s guest. She talked about the process of evaluating the plants entered in the Trial Gardens and her results can be found here.
Just to make you feel the Spring has arrived here’s information on tomatoes.
What is causing those holes in the ground? Could be Mining bees, an important pollinator.
Dave in Macomb Township‘s yard is being overrun with what sounds like bentgrass. The first step is to positively identify the problem grass and this key from NC State is easy to use. If it is bent grass, Tenacity is very effective, but expensive and used in very small amounts so I recommend contacting a lawn care company to apply the material. If you want to reseed, you can kill off any leftover sod and slit seed directly into the old sod. If you want to resod, rent a sod cutter and get take off the old material, till the area and put down new sod. Dave also wondered about rolling a yard to get rid of soft spots. My concern with rolling is that too heavy a weight on moist soil can cause compaction that severely limits room development. If you decide to roll your yard, I suggest not adding any weight to the roller and make sure the soil has dried out at least 6 inches deep.
Matthew from Ypsilanti’s yard was very uneven. Adding (top dress) screened topsoil 1/2 inch at a time over a period of months will help. Here’s information. If moles are causing a problem here’s how to get rid of them.
Thinking about reseeding your lawn; be careful using weed control products. Here’s more information from Dr. Kevin Frank.
Having a tiger prowling your flower beds is a good thing.
Removing a maple tree sucker and white pine decline.
Preventing wild fires in your neighborhood. Information from MSU.
Carol from Grosse Pointe called about what sounded like lichens on her hawthorn and other trees. Lichens are harmless and grow in moist, shady areas, including tree trunks.
Bob from Garden City was trying to get rid of some very aggressive Baltic Ivy without using glyphosate. You can use what are called “burn down” materials, some of which are certified organic. These materials don’t kill the roots so you should manually remove as much of the tops as possible and apply every time a new shoot appears. The goal is to starve the roots so they don’t regrow which takes time and persistence.
When looking for plant information one of the best resources are your local, family owned nurseries and garden centers such as Barson’s in Westland who are celebrating 38 years in business.
Carol in Madison Heights was finding ants in her home and hoped they weren’t Carpenter ants which can cause significant damage. Since there are several types of ants that resemble Carpenter ants, the first step is to submit a sample to Macomb County MSU Extension or Diagnostic Services on campus to have them identified.
John in Troy‘s water garden is infested by muskrats. Since these are wild animals you should contact the Michigan Department of Natural Resources to see what you can do to prevent further damage.
Jan in Clarkston was wondering how to control Carpenter bees.
Dave in Milford can’t get rosemary to grow in the house and neither can I. The University of Illinois recommends planting rosemary in pots if you plan to bring them inside and putting them in a cool, sunny location in your house. They are very sensitive to overwatering.
Linda in Brownstown wanted information on irrigation systems.
Enjoy the MSU Student Horticulture Association’s Spring Show Saturday April 21 and Sunday, April 22.
The MichiganGardener magazine is a wonderful resource for gardeners in Southeast Michigan. If you haven’t pick one up at your favorite garden center, you can read it on line.
Was your grass flooded this winter? Here is information from Dr. Kevin Frank.
Never planted a tree before? Here’s how.
Reseeding or resodding your lawn this spring? Get help from MSU’s Green Team.
Help prevent the spread of oak wilt. Don’t prune.
Want to become an Integrated Pest Management expert? Take a course at MSU’s Integrated Pest Management Academy.
Spring can’t come fast enough? Visit a butterfly house
Boxelder bugs have been plaguing many this winter.
Beside tulips and daffadils, Hairy Bittercress is blooming.
Your beds turning purple? Could be Purple Deadnettle.
Time to control White Pine Weevil.
Conifers turning brown due to winter damage.
The latest MSU information for controlling grubs in your lawn.
Time to apply crabgrass preemergent materials? More information here.
Boxwoods turning brown? Could be boxwood leafminer.
Carol from Novi asked about the difference between “potting soil” and “potting mix”. While Bobbi pointed out these terms are using interchangeably, potting mix contains large peat moss particles (you can see plant parts) and amendments such as vermiculite or perlite; is quite light and porous; is sold by the cubic foot and is recommended for use in containers. The material in potting soil is very fine (can’t tell if it came from a plant); may or may not contain amendments; is sold by the pound and holds too much water to be used in containers. Here’s more information.
CONTACT DR. DEAN KRAUSKOPF