Don't Rush Your Spring Cleanup!

Eryngium (rattlesnake master) does double duty in the gardenit has a great seed head and hollow stems.
Photograph provided by Olbrich Botanical Gardens

Spring is right around the corner. Do you feel like somehow your garden chores are already stacking up? With so much to do, you may be tempted to get a jump-start on your spring garden cleanup, but be patient. There are many benefits to delaying your cleanup process and some environmentally friendly factors to keep in mind.

Soil Structure
Rushing into your perennial beds could lead to compacted soils. You never want to work in the soil when it’s too wet, especially in clay-type soils. Instead, use the time to prepare for the busy gardening season by cleaning and sharpening your tools. With a short growing season, wouldn’t you rather spend your time gardening than fixing tools? Clean tools last longer and help prevent the spread of pests and diseases around your garden. Proper maintenance will also save you time and money in the end.

Unpredictable Weather
Remember those mid-April snowstorms that seem to be happening more and more? Wisconsin definitely has some harsh, random weather. As an extreme example, we can look to the Lake Monona historical records. According to the Wisconsin State Climatology Office, the latest opening date (when the lake thawed to an observable 50 percent ice cover) was May 4, 1857. If you remove all the dead foliage from your perennials and grasses too early, you’ll expose the crown of the plant to extreme temperatures or fluctuations with no insulation around their root zone. Even hardy, cold-tolerant plants appreciate a natural blanket at this time of year.

Leave Your Leaves
Does it really make sense to remove every single leaf just for you to mulch again in upcoming weeks? No! Leaf litter, long grass, and brush piles are critical components in your garden. Leaves decompose and add important organic matter to your soil. Fallen leaves provide shelter for insects, which are rich in protein and a necessary food for birds, especially as they’re raising their young. Beneficial insects, like ladybugs, lacewings, and soldier beetles, are hibernating in your leaves. If you let them be, once they wake up from their winter slumber, they’ll help you battle common garden pests without the use of chemicals. Long grass and brush piles are highly attractive to our feathered friends, providing nesting material and protection from predators while foraging.

Seed Heads for Birds
Hopefully, you left some perennial and grass foliage in your garden for additional winter interest. Now let them stand just a little bit longer. Both migrant and winter birds rely on native perennial and grass seeds. When food sources are scarce, foraging birds, such as sparrows, towhees, buntings, chickadees, nuthatches, and finches, will appreciate a smorgasbord of seeds to choose from. Plus, it’s fun watching them!

Hollow Stems for Bees
Solitary nesting native bees are often overlooked, but pollinate plants more efficiently than European honeybees. Thirty percent of North American native bees are cavity nesters that lay their eggs in the hollow stems of plants, including mason and leafcutter bees. It’s best to leave hollow-stemmed plants standing as long as possible into the spring. These unique plants could be housing hundreds of native bees and beneficial insects who are overwintering, hunkered down inside the stem as either adults or pupae.

Did you know that the female adult bee determines the sex of the egg when she lays it? The females take longer to develop and, therefore, are deposited into cells at the back of the tunnel or stem so that the males will hatch first. The males are then ready and waiting to mate when the females finally emerge.

Bee Gentle
When you start your cleanup, don’t overdo it. During spring garden-maintenance chores, try to minimize disturbances. Don’t cut your plant stems and branches into small pieces—there may be sleepy bees in there! Instead, leave the plant material as intact as possible, cut grasses 8 to 12 inches from the ground, and keep them as long stalks. Gently toss plant material onto your compost pile or spread out loosely along your fence line. This method will allow any insects taking shelter inside to emerge when the time is right.

Plants with Hollow Stems
• Allium
• Baptisia
• Eryngium
• Eutrochium (Eupatorium)
• Fargesia
• Forsythia
• Helianthus
• Persicaria
• Rubus
• Sedum

Plants with Great Seed Heads
• Allium
• Coreopsis
• Echinacea
• Helianthus
• Monarda
• Oligoneuron (Solidago)
• Panicum
• Rudbeckia
• Sedum
• Symphyotrichum (Aster)

Dates to Keep in Mind When Deciding When to Do Your Garden Cleanup
Zone 5: April 15 or later, if possible
Zone 4: May 1
Zone 3 or colder: May 15
Visit to determine your zone.

Katey Pratt is a horticulturist at Olbrich Botanical Gardens.

Photographs provided by Olbrich Botanical Gardens.

Olbrich Botanical Gardens
3330 Atwood Avenue
Madison, WI 53704