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June is National Perennial Gardening Month — and for good reason. The soil is warm, the weather is stable, and the threat of frost is finally, truly behind us. We can kiss goodbye to unpredictable May and welcome the peak of blooms, the best planting conditions of the year, and yes — the maintenance that comes with it.

June is when gardens hit their stride. Perennials are blooming, annuals are filling in, vegetables are sizing up, and everything is growing faster than you can keep up with. It’s exciting. It’s also a lot.

Here’s our breakdown to keep it simple and manageable so you can make the most of the growing season — and actually spend time outside enjoying it instead of just working in it.

Home: Bring the Indoors Out

June is the month to fully commit to outdoor living. Dust off the patio furniture, move plants outside, and create spaces you want to spend time in.

Clean Off Patio Furniture

It’s been sitting all winter. Give it a good wipe-down, check for loose screws or wobbly legs, and make it inviting again. Add cushions, throws, or outdoor pillows if you want it to feel like an outdoor room instead of just a place to sit.

Get Container Gardens, Herbs, and Succulents on the Patio

If you haven’t already, move your container gardens, potted herbs, and succulent arrangements outside. June’s warmth and longer days make everything thrive. Place containers near seating areas, by doorways, or anywhere you want a pop of color and life.

Move Houseplants Outside for the Summer

Many houseplants benefit from spending summer outdoors. The increased light, fresh air, and natural humidity help them grow stronger and healthier.

• Houseplants that love summer vacation: Snake plants, jade plants, spider plants, birds of paradise, monstera, pothos, ferns
• Important: Acclimate them slowly. Don’t move houseplants directly from indoors to full sun — they’ll sunburn. Start by placing them in a shaded or partly shaded spot for a couple of hours a day, then gradually move them to brighter locations for longer periods of time. Most houseplants prefer bright, indirect light or dappled shade outdoors, not full blazing sun.

Bring them back inside before temperatures drop below 50°F in fall.

Garden: Plant, Divide, Fertilize, Repeat

June is peak planting season and peak growing season, which means your garden needs consistent attention to keep everything thriving. To lighten the load, remember being in the garden is also a wonderful family activity for small hands or kids on break.

Direct Sow Summer Vegetables

The soil is warm, and summer vegetables are ready to go in the ground. 

• Direct sow these crops now for a mid-to-late summer harvest: Beans, cucumbers, summer squash, beets, carrots
• Stake as needed: Cucumbers, beans, and squash all benefit from support. Set up trellises, cages, or stakes at planting time so you’re not disturbing roots later.

Prime Time for Annuals

June is the best month to plant annuals in containers and garden beds. They’ll establish quickly in the warm soil and bloom all summer long. If you haven’t filled your containers or garden beds yet, now’s the time.

Time to Replace and Fill In Perennials

Now that we have a clear picture of what came back and what didn’t, June is perennial planting month. Fill in gaps, replace plants that didn’t make it, and add new varieties you’ve been eyeing.

• And here’s the thing: If some of your perennials didn’t come back, don’t feel like a failed plant parent. Gardening is trial and error. Sometimes plants don’t thrive where you thought they would. Soil, drainage, microclimates, harsh winters — there are a hundred reasons a plant might not make it, and most of them have nothing to do with you.

Try something new. Observe what happens over this growing season. That’s how you learn what actually thrives in your yard.

Finish Dividing Perennials by Mid-Month

If you didn’t get to dividing perennials in early spring, you have until mid-June to finish. After that, the heat makes it too stressful for plants.

Why divide before peak heat:

• Plants establish faster in moderate temperatures
• You’ll need to water less than if you divide in July or August
• Plants have time to recover before the stress of midsummer heat

Perennials that can still be divided in early June: Hostas, daylilies, heuchera, iris (after blooming)

Reapply Preen (If You Used It in Early Spring)

If you applied a pre-emergent weed preventer like Preen 9–12 weeks ago (late March or early April), it’s time to reapply for continued protection. This keeps new weeds from germinating through the rest of the growing season.

Fertilize Regularly to Keep Blooms Coming

Containers, annuals, and heavy feeders like tomatoes and roses need regular fertilizing to perform their best. Use a liquid fertilizer every 1–2 weeks, or apply a slow-release granular fertilizer once a month.

Pair fertilizing with deadheading annuals for best results. Removing spent blooms signals the plant to produce more flowers, and feeding gives it the energy to do so.

Apply Sawfly Spray If Needed

Sawfly larvae (which look like caterpillars) can defoliate pine, spruce, and other evergreens in a matter of days. If you notice clusters of small green larvae or sudden needle loss on evergreens, treat with an insecticidal soap or spinosad-based spray. 

Act fast — sawflies work quickly. Visit us in-store for products and expert advice.

Get Perennials Up at the Cabin

If you have a cabin or second property, June is the perfect time to plant perennials there. The soil is warm, conditions are stable, and you’ll have blooms to enjoy all summer — right where you want to be.

Landscape: Prune, Mulch, Water Smart

June is prime time for landscape maintenance — pruning spring bloomers, mulching to retain moisture, and establishing smart watering habits for the summer ahead.

Get in the Habit of Watering in the Morning

Morning watering is a summer best practice for all plants — garden and landscape. Here’s why:

• Reduces evaporation: Water has time to soak into the soil before the heat of the day
• Prevents fungal disease: Foliage has time to dry before evening, reducing the risk of mildew and other fungal issues
• Gives plants a head start: Watered plants handle heat stress better

Aim to water before 10 AM if possible.

Mulch to Retain Moisture as Temps Increase

A 2–3 inch layer of mulch around trees, shrubs, and perennial beds helps retain soil moisture, suppress weeds, and regulate soil temperature during heat waves. If your mulch has thinned out over the past year, top it off now before summer heat kicks in.

Prune Spent Spring Blooms

Spring-flowering shrubs bloom on “old wood” — branches that grew the previous year. Once they finish blooming, prune them to shape and encourage next year’s growth.

Prune these shrubs in June after blooms fade:

• Lilac (2 week window to prune after they bloom before they start next years flowers)
• Forsythia
• Azalea
• Chokeberry
• Magnolia
• Redbud
• Bridal wreath spirea

Don’t wait too long — if you prune these shrubs in late summer or fall, you’ll cut off next year’s flower buds.

General Landscape Pruning

June is also a good time to shape evergreens and deciduous trees if needed.

Safe to prune in June:

• Junipers
• Arborvitae
• Wisteria (after blooming)
• Maples (only if necessary — avoid heavy pruning)
• Birch (only if necessary — avoid heavy pruning)

Avoid heavy pruning of maples and birch unless absolutely necessary. They “bleed” sap when cut, which isn’t harmful but can be messy.

Carve Out a No-Maintenance Corner

Don’t let summer go by wishing you had a low-maintenance native planting. If you’ve been thinking about replacing that bare patch where nothing grows with native wildflowers and grasses, now’s the time to do it.

Get in touch with our landscape design and build team and let the pros take care of it for you. We’ll design and install a native prairie planting with wildflowers and grasses that need nothing but watering to get established — and once they’re settled, they take care of themselves.

It’s easier than you think, and it looks better than that bare patch you’ve been staring at all spring.

What’s Happening at Sunnyside

June is our busiest month at the garden center. The greenhouse is fully stocked with annuals, perennials are in peak bloom, vegetable starts are available, and our garden and landscape teams are installing projects all over the Twin Cities.

If you’re planning to plant this month — and you should be — stop by early in the day or on weekdays if you can. Weekends are wonderful and chaotic, but our team is always here to help you find what you need, answer questions, and load your car.

The Beauty of June

June is when everything you’ve been waiting for finally happens. The garden is lush. The weather is warm. The days are long. It’s the peak of the growing season, and it’s worth savoring.

Yes, there’s maintenance. But there’s also morning coffee on the patio surrounded by blooms, tomatoes starting to set fruit, hummingbirds visiting your containers, and the deep satisfaction of watching something you planted grow.

Don’t just work in your garden this month. Spend time in it. Sit in it. Enjoy it. That’s what June is for.