BLog

April in Minnesota is the month gardeners have been waiting for. The ground thaws, the air warms, and something shifts — not just in the garden, but in us. It’s a month of action after a long winter of dreaming, a time when planning gives way to planting and careful watching turns into real work.

At Sunnyside Gardens, April is when things get busy. The greenhouse fills, the parking lot gets crowded, and questions fly. Here’s your comprehensive guide to what you can — and should — be doing in the garden and landscape this month.

Garden: Clean, Divide & Plant

April is when the garden truly begins. The ground is workable, the air is warming, and there’s plenty to do.

Cut Back Perennials (Wait for 50°+)

If you left perennials standing for winter interest, you can cut them back — but wait for a full week of temperatures consistently above 50°F. Here’s why: beneficial insects, pollinators, and garden critters are still sheltering in stems and leaf litter. Disturbing them too early harms the very creatures that help your garden thrive.

When you do cut back, consider leaving the trimmings in a pile so beneficial insects have a safe place to emerge. Once they’ve had time to move on, you can compost the debris or use it as mulch.

Divide Perennials

Early spring is the ideal time to divide overgrown perennials before they put on too much growth. Dig up the clump, separate it into smaller sections with roots attached, and replant immediately. Water well to help them establish.

Perennials to divide now:

• Hostas
• Daylilies
• Nepeta (catmint)
• Monarda (bee balm)
• Garden phlox

Clean Out Garden Beds (Once Temps Are Above 50°)

Once temperatures are consistently above 50°F, you can begin cleaning out beds. Gently remove heavy debris, pull back protective mulch from emerging perennials, and refresh mulch layers as needed. Add compost or aged manure to beds to improve soil structure and fertility.

Avoid working wet soil — if it sticks to your boots or forms a muddy ball when squeezed, wait a few more days. Working wet soil compacts it and damages structure.

Remove Winter Protection

As perennials begin to emerge, gently pull back protective mulch (leaves, straw, wood chips) from the crowns to allow new growth to come through. Leave mulch on the soil around plants, about 3-4 inches diameter helps to moderates soil temperature, retains moisture, and suppresses weeds.

If temperatures are still dipping into the low 20s at night, you can push mulch back over tender perennials temporarily for protection.

Install Peony Cages

Peonies are emerging now, and it’s easier to install support cages while they’re still small. Place the cage over the plant when shoots are just a few inches tall — as the plant grows, the foliage will fill in and hide the structure. This prevents heavy blooms from flopping over later in the season.

Landscape: Prune, Protect & Prepare

April is one of the busiest months in the landscape. Trees and shrubs are waking up, and there’s plenty to do — carefully.

Prune Shrubs and Trees

April is a good time to prune certain shrubs and trees, but there are important exceptions.

What you CAN prune:

• Dogwoods
• Hedges (trim lightly to shape)
• Roses (cut back dead wood and shape)
• Summer-blooming shrubs

What you should NOT prune:

• Oaks (April–October): The fungus that causes oak wilt is most abundant from April through October. Pruning oaks during this time puts them at serious risk. Wait until late fall or winter.
• Spring-flowering shrubs like lilacs, forsythia, and azaleas — wait until after they bloom, or you’ll cut off this year’s flowers.

Before you prune: Check carefully for pollinators, cocoons, and chrysalises sheltering in branches. If you find them, wait or prune selectively to avoid disturbing them.

Apply Weed Preventers and Animal Repellents

Now is the time to apply pre-emergent weed preventers to garden beds and around perennials. These products prevent weed seeds from germinating, but they must be applied before weeds sprout.

If deer, rabbits, or other animals browse your garden, apply repellents now — especially around emerging bulbs like tulips and hostas. Reapply after heavy rain.

Lawn Care: Wait Until Conditions Are Right

April lawns need patience, not heavy intervention.

Avoid Raking and Heavy Lawn Work

Wait until temperatures are consistently above 50°F and the ground has dried out and firmed up before raking or walking heavily on the lawn. Wet, dense soil compacts easily, and dormant grass is fragile. Pollinators are also still sheltering in thatch and bare soil — disturbing them too early harms biodiversity.

If you notice snow mold (grayish-white patches), gently rake the affected areas to improve air circulation once the ground is dry.

Treat Crabgrass as It Emerges

Crabgrass begins germinating when soil temperatures reach 55-60°F (typically late April in the metro). Apply a pre-emergent herbicide now to prevent it from taking hold. 

Hold Off on Fertilizer

Don’t apply fertilizer or herbicides until grass is actively growing and you’ve mowed at least twice. Early April is too soon — you risk feeding weeds more than grass.

What’s in Stock at Sunnyside in April

Here’s what’s waiting for you this month:

• Cool-season vegetables: Like lettuce and kale
• Pansies and violas: Ready to plant now
• Seeds: Full selection for direct sowing and indoor starting
• Soil, mulch, and weed preventers: Everything you need to prep beds
• Spring containers: Pre-made or DIY — we have it all

The Big Picture

April is the month when winter finally lets go and the garden becomes yours again. It’s a month of possibility, of getting your hands dirty, of watching things wake up and begin again.

The work is real now — not just planning, but planting. And there’s a particular kind of satisfaction that comes from being out there, sleeves rolled up, soil under your nails, breathing in air that smells like spring.

At Sunnyside Gardens, we’re here to help you make the most of it. Stop by, ask questions, and let’s grow together.