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Mother’s Day in Minnesota isn’t just a holiday —it’s the official green light. The moment we’ve all been waiting for. The day we finally trust that winter is truly behind us and we can plant everything and anything without second-guessing ourselves.

This includes our beloved summer annuals, tender perennials, and yes — succulents for patio season. At Sunnyside, we love staging outdoor spaces with succulent arrangements, and May is when they finally get to shine. If you’ve been eyeing those gorgeous aeonium and jade plants in the greenhouse, now’s the time to bring them home.

May is the busiest, most hopeful month in the gardening calendar. The ground is warm. The threat of frost has passed. And there’s so much to do — in the best possible way.

Here’s your guide to making the most of May in your garden.

Garden: Getting in the Dirt

Finish Spring Clean-Up

If you haven’t already wrapped up your spring cleanup, early May is your last chance before things really take off. Cut back any remaining dead perennial stems, rake out garden beds, and clear away winter debris. The cleaner your beds are now, the easier the rest of the season will be.

Divide Fall Blooming Perennials

Early spring — as new growth emerges but before plants are in full bloom — is the ideal time to divide perennials. Dividing rejuvenates crowded plants, improves blooming, and gives you extras to fill in bare spots or share with neighbors.

Perennials that respond especially well to spring division:

1. Hostas
2. Lilies
3. Heuchera (coral bells)
4. Shasta daisies
5. Yarrow

Water as Needed

Spring rains usually do the heavy lifting in May, but if we hit a dry spell, newly planted trees, shrubs, and perennials need consistent moisture to establish. Water deeply and less frequently rather than shallow daily watering — this encourages deep root growth.

Mulch Garden Beds

Mulch is one of the best things you can do for your garden. It suppresses weeds, retains moisture, regulates soil temperature, and breaks down over time to improve soil health. Apply 2–3 inches of shredded bark, wood chips, or composted leaves around plants, keeping mulch a few inches away from stems and trunks to prevent rot.

Start Weeding Regularly

Weeds are easier to pull when they’re small. Get in the habit of walking your garden beds weekly and pulling anything that doesn’t belong. A few minutes now saves hours later!

Start the Planting Party

Once we’re past the average last frost date (typically May 15 in the Twin Cities, though it varies by year and area), you’re free to plant:

1. Summer annuals: impatiens, herbs, begonias, coleus, geraniums
2. Tender annuals: dahlias, petunias, lantana
3. Direct-sow summer vegetables: beans, squash, cucumbers, corn, carrots
4. Summer bulbs: dahlias, elephant ears, canna lilies
5. Begin fertilizing: Feed perennials, shrubs, and containers with a balanced slow-release fertilizer or compost

This is also when you can safely move houseplants outside for the summer and stage those succulent arrangements on your patio.

Landscape: Time to Start Maintenance

May Pruning Guide

Pruning in spring and early summer serves different purposes depending on when you do it. Here’s what to prune — and when.

Mid-Spring: Early May
Active growth has begun, and pruning now is ideal for shaping plants and encouraging more blooms.

Plants to prune in mid-spring:

1. Junipers
2. Roses (remove dead or damaged canes, shape as needed)
3. Yews
4. Hedges (light shaping to encourage dense growth)

Late Spring: Late May–Early June
Most trees and shrubs have fully leafed out, and you can clearly see what’s healthy and what’s not.

Plants to prune in late spring:

1. Arborvitae
2. Maples (prune only if necessary — avoid heavy pruning during heat spikes)
3. Birch (prune only if necessary — avoid heavy pruning during heat spikes)

Important note: Avoid heavy pruning of maples and birch during heat spikes. These trees “bleed” sap when cut in spring, which isn’t harmful but can be messy. If you need to prune them, do it quickly and limit cuts to what’s necessary.

Spring: May–June (Immediately After Blooms Fade)
Spring-flowering shrubs bloom on “old wood” — branches that grew the previous year. If you prune them too early, you’ll cut off this year’s flowers. Wait until blooms fade, then prune to shape and encourage next year’s growth.

Plants to prune after spring blooms fade:

1. Lilac
2. Bridal wreath spirea
3. Forsythia
4. Azalea
5. Chokeberry
6. Magnolia
7. Redbud

Pruning these shrubs right after they finish blooming gives them the rest of the growing season to develop next year’s flower buds.

Start Lawn Care

When soil temps are above 50°F or when forsythia bloom for a visual queue, it’s time to apply crabgrass pre-emergents and lawn seed. Note: Do not apply weed control if you are seeding.

Once grass is actively growing and taller than 2-3 inches, you’re good to begin mowing. Waiting for active growth helps encourage deep rooting, helps to shake out weeds, and gives pollinators time to wake up.

What’s Happening in the Garden Center

May is our busiest time of year at Sunnyside Gardens, and for good reason. The greenhouse is overflowing with color — hanging baskets, annual flats, perennials in full bloom, vegetable starts, herbs, and gorgeous container gardens.

If you’re planning to plant this month (and you should be), come early in the day or on weekdays if you can. Weekends are wonderful and chaotic — everyone has the same idea. Our team is here to help you find what you need, answer questions, and load your car with plants that are ready to thrive.

Mother’s Day weekend is the unofficial start of gardening season, and the energy in the greenhouse is contagious. Bring the family. Make it a tradition. Pick out plants together and start building the garden you’ve been dreaming about all winter.

The Beauty of May

May is the month when everything feels possible. The perennials you planted last year are coming back stronger. The shrubs are blooming. The soil is warm enough to work. And suddenly, after months of waiting, you can finally plant everything you’ve been eyeing in the greenhouse.

It’s the green light. The starting gun. The moment we’ve all been waiting for!

Get your hands in the dirt. Divide those hostas. Mulch your beds. Plant those annuals. And don’t forget to stage a few containers on the patio — because if there’s one thing May teaches us, it’s that the waiting is over.

Time to get dirty!