AYGQ: LIVE – March 2026 Session Links and Resources

Fruits & Vegetables

Apple Trees

Q-Four honey crisp apple trees were diagnosed with root rot. What should I do this spring to prevent root rot from starting again? 
A-Root/collar rot is associated with poor drainage and low areas; homeowners have limited chemical options. Improve drainage and grade so water moves away from trunks. If replanting, choose resistant/tolerant rootstocks (e.g., Geneva series) and avoid chronically wet sites.

• Root and Crown Rots – wisc.edu

Asparagus

Q-What is the best fertilizer to put on an asparagus bed and when is the best time to put it on?
A-It depends on the age your asparagus patches. If your plants are less than 4 years, you can fertilize in spring using 10-10-10. After 4th year, delay fertilizing until after final harvest in June.

• Growing Asparagus in Home Gardens – umn.edu

Cucumber, Tomatoes and Raspberries

Q- They looked like they needed water, but it had just rained as time went on, they just kept wilting. 
A-Were these plants watered on a regular basis or just when it rained?  Verticillium can cause chronic wilting and decline; confirm by lab diagnosis before you replant the same crops repeatedly.  Use resistant varieties where available, rotate away from susceptible hosts, and ensure proper irrigation and fertility per soil test results. 

• Verticillium Wilt of Vegetables – wisc.edu
• Best Practices for Watering Yards and Gardens (Video) – wisc.edu
• Plant Disease Diagnostic Clinic – wisc.edu
• Homegrown Tomatoes for Wisconsin – wisc.edu
• Growing Raspberries in Wisconsin – wisc.edu
• Growing Cucumbers in Home Gardens – umn.edu
• Using Crop Rotation in Home Vegetable Gardens – wisc.edu
• Soil Testing for Successful Gardens – wisc.edu

Hazelnuts

• Emerging Crops Lunch & Learn (Video) – wisc.edu

Pear Tree

Q-Does a very old pear tree require fertilizing?  If so, should fruit tree spikes be used? 
A-Start with a soil test to determine if fertilization is needed at all; mature pears generally need little to no added fertilizer unless a deficiency is documented.  Focus on corrective pruning to open the canopy for light and air. Spread major structural corrections over multiple years and sanitize pruning tools between cuts. Tree spikes can push excessive vegetative growth (water sprouts), which reduces light penetration and can further suppress flower bud formation and fruiting. 

• Soil Testing – wisc.edu
• Growing pears in Wisconsin – wisc.edu
• Pruning Pears – umn.edu
• Cleaning and Disinfecting Pruning Tools for Orchard Crops – missouri.edu

Raspberries

Q-Will raspberries grow when planted 8 inches from a garage wall?
A-It can work if plants show good vigor and fruiting. If growth is weak (heat reflection, root restriction), relocate to an open, well‑drained full‑sun row with support and mulch.

• Growing Raspberries in Wisconsin – wisc.edu
• Black Walnut Toxicity – wisc.edu

General Gardening

Ornamental Grasses

Q-Do Karl Foerster, Little Bluestem and Prairie Dropseed plants need to be burned to survive? 
A-No. In home landscapes, burning is not necessary. Instead, cut grasses back to ~3–4 inches in late winter/early spring before new shoots emerge. Warm‑season species (e.g., little bluestem, switchgrass, prairie dropseed) green up late; removing old foliage in spring prevents shading of new growth.

• Gardening with Ornamental Grasses – wisc.edu

Seed Starting Grow Lights

Q-When should grow lights be turned on, how high, and best types? 
A-Turn lights on at sowing or immediately at emergence; provide 12–14 hours of light per day using a timer. Modern LEDs are preferred for efficiency and spectrum. Start fixtures ~6 inches above seedlings and raise them as plants grow to keep light intense but avoid heat stress.  Use reputable fixtures with good warranties; ensure adequate air movement and avoid overwatering to prevent damping-off.  

• Indoor Lighting Options – umd.edu
• Starting Seeds Indoors – umn.edu
• Damping Off – wisc.edu

Seed Starting Medium

Q-What’s the best seed-starting medium?
A-Use sterile, lightweight seed‑starting or high‑quality potting mixes. Avoid reusing last year’s potting mix or garden soil to prevent disease and compaction.  Begin diluted liquid fertilization when seedlings reach 3–4 inches tall; maintain even moisture and strong light to prevent damping-off.

• Indoor Lighting Options – umd.edu
• Starting Seeds Indoors – umn.edu
• Damping Off – wisc.edu

Houseplants

Ficus (Weeping Fig)

Q-Ficus has dropped most of its leaves.  Should it be pruned back? 
A-Ficus commonly defoliates after changes in light, humidity, or drafts during winter. Increase humidity, provide bright light, and water conservatively. Use the scratch test to confirm deadwood; prune only dead branches and allow the plant to refoliate as conditions improve.

• Houseplant Care – wisc.edu
• Ficus – ncsu.edu

Rubber Tree

Q-How to cut it down and root the top? 
A-Do an air-layering in late spring.

• Propagating Houseplants – psu.edu
• Houseplant Care – wisc.edu

Insects

Cold Weather’s Effect on Pests

Q-Will extreme cold or late snows kill plant diseases or insects?
A-Most plant pathogens overwinter in debris or soil and resume activity when conditions warm; cold snaps do not “sterilize” garden soils. Likewise, many insects are well adapted to Wisconsin winters via dormant stages; expect them to rebound once temperatures stabilize. 

Boxelder Bugs

Q-They keep coming back covering the whole south side of my house and still getting inside after completely replacing and sealing siding and windows.  
A-Population spikes often follow dry summers. For prevention, focus on sealing gaps/cracks, repairing screens, and consider exterior repellent sprays in late summer.  Indoors: vacuum rather than spray. Outdoor sanitation (removing seed accumulations) can help reduce nearby breeding sites.

• Boxelder Bug – wisc.edu

Japanese Beetles

Q-Ficus has dropped most of its leaves.  Should it be pruned back? 
A-Systemics can protect foliage but carry pollinator exposure risks. Do not apply neonicotinoid systemics to lindens (Tilia), where labels prohibit use. On smaller plants, prefer non‑systemic options (hand‑picking, covers); mature trees tolerate some defoliation without long‑term harm.

• Japanese Beetle – wisc.edu

Jumping Worms

Q-Do cold winter temperatures affect jumping worms? 
A-Jumping worms overwinter as resilient cocoons and can also overwinter in various life stages; typical winter cold does not reliably eliminate them.

• Jumping Worms – wisc.edu

Lily Leaf Beetle:

• Lily Leaf Beetle – wisc.edu

Squash Bugs

Q-Is there anything I can do early season to prevent them on my butternut squash and zucchini? 
A-Adults overwinter in sheltered spots; there is little you can do in late winter beyond cleaning up debris. The key is early detection of eggs and nymphs starting late June.  Use cultural tactics (residue removal, crop rotation), hand-remove eggs. 

• Squash Bugs – wisc.edu
• Growing Degree Days – wisc.edu

Map for invasive viburnum leaf beetle and other invasive insects in Wisconsin

• Wisconsin Invasive Insect Maps – wisc.edu
• Viburnum Leaf Beetle – wisc.edu
• Viburnum Borer – wisc.edu

Wireworms

Q-What is the best insecticide for wireworms in potatoes and carrots available to a homeowner?
A-Wireworms are click beetle larvae common in sites that were previously sod or grassy; damage often persists several years and is worse in heavy, cool, moist soils. There are no consistently effective homeowner insecticides. Emphasize cultural tactics: strong weed/grass control, rotate crops.

• Wireworms – wisc.edu
• Click Beetles – wisc.edu

Lawns

There were no questions on lawns this month.

Plant Diseases

Cold Weather’s Effect on Pests

Q-Will extreme cold or late snows kill plant diseases or insects?
A-Most plant pathogens overwinter in debris or soil and resume activity when conditions warm; cold snaps do not “sterilize” garden soils. Likewise, many insects are well adapted to Wisconsin winters via dormant stages; expect them to rebound once temperatures stabilize. 

Peach Leaf Curl

• Peach Leaf Curl – wisc.edu

Verticillium Wilt

Q-Can a new magnolia be planted in the same location where one died of Verticillium Wilt? 
A-These fungi are commonly found in Wisconsin soils and in roots, branches and leaves of infected plants. Choose species/cultivars with resistance or immunity to Verticillium; avoid replanting with highly susceptible hosts. Improve site health, irrigation, and mulch for plant vigor. 

• Verticillium Wilt of Trees and Shrubs – wisc.edu

Trees & Shrubs

Austrian Pine

Q-The needles are 1/2 green (the base) and brown (the tips). 
A-The classic pattern of green needle bases with brown tips fits Dothistroma needle blight; winter injury can appear similar, so lab confirmation is important. 

• Dothistroma Needle Blight – wisc.edu
• Plant Disease Diagnostic Clinic – wisc.edu

Arrowwood Viburnum

Q-Newly planted shrub isn’t growing well. 
A-Minimal growth the first two years can be normal (Year 1 acclimation; Year 2 root growth). Verify planting depth and loosen circling roots at planting. In parts of Wisconsin, Viburnum Leaf Beetle is established; monitor leaves in spring and early summer for skeletonization. 

• Arrowwood Viburnum – illinois.edu
• Wisconsin Invasive Insect Maps – wisc.edu
• Viburnum Leaf Beetle – wisc.edu
• Viburnum Borer – wisc.edu

Crabapple Trees

Q-Due to the large amount of snowfall this week in western Wisconsin, it’s difficult to get to the trees to prune.  How long will it be safe to trim trees this spring? 
A-Typically, you can continue dormant pruning through ~early April. Keep an eye out for “green tip” or when buds begin pushing out new growth. You’ll want to hold off on major pruning when that happens as pruning wounds may be susceptible to diseases. 

• Pruning Deciduous Trees – wisc.edu

Weeds & Invasive Species

Bindweed

Q-How do you eliminate bind weed from the garden? 
A-In mixed plantings rely on persistence: frequent pulling/cutting to exhaust roots and prevent seed set.  Spot‑treatments risk injury to desirable plants; consider edging/barriers and mulches where feasible.

• Bindweed – psu.edu

Wildlife

Moles

Q-Any suggestions for another way to get rid of a mole infestation in the garden? Our soil is a sand and we use granulated lime.
A-Check for surface tunnels (confirm by stomping and checking for repair within 24 hours). Improve lawn health to reduce grub prey; repellents provide mixed results, and poisons pose risks to non‑targets.

• Moles – wisc.edu
• White Grub control in turfgrass – wisc.edu

Slugs

Q-Do copper posts deter slugs? 
A-Copper posts/strips have inconsistent performance in gardens. For reliable reduction, combine sanitation and trapping with labeled slug baits used per directions.

• Slugs – wisc.edu

Squirrels

• Squirrels – widencdn.net

Wildlife Ecology Factsheets

• UW Wildlife Ecology factsheets – wisc.edu