You found the perfect hydrangea at the nursery...but it’s the middle of summer. Should you plant it now or wait until fall? You can plant it now, but only if you do it one specific way: plant it in a pot. Otherwise, intense heat can leave your new shrub struggling before it has a chance to establish.
Technically, the best time to plant a hydrangea is in early fall—once the nights have turned cool but before there’s any risk of frost. This timing allows the root system to get established without the danger of heat waves drying it out, and before frost can damage the young roots.
But since it’s the middle of summer and everyone else has blooming hydrangeas, we get that you want to add one to your garden now, and you can’t wait for the fall planting season. Here’s how to do it.
Only Plant in a Pot
If you’re eager to plant a hydrangea now, be prepared to give it a lot of water to help it get established. Your best option may be to plant it in a pot. That way, on hot, dry days, you can move it to a shadier spot.
How to Plant a Hydrangea in a Pot
Hydrangeas grow well in pots and are ideal for small spaces like porches or patios. Start by selecting a container that’s weather- or frost-proof (to prevent cracking in winter) and at least 16 inches—ideally 24 inches—in diameter. Once filled, a pot this size will be heavy, so consider placing it on rollers to make it easier to move.
While any hydrangea can be grown in a pot, choosing a compact or dwarf variety will reduce the need for frequent pruning. Fill the pot with enough soil so that the plant sits about 2 inches below the rim. Place the hydrangea in the pot, then fill in around the root ball with soil. Water thoroughly. If the soil settles after watering, top it off with more soil.
Since potting soil dries out quickly, check the moisture level often. If the top inch feels dry, water until it runs out of the drainage holes at the bottom.
Important: Don’t move potted hydrangeas indoors during winter. They need to experience regular winter dormancy—which is triggered by cooler temperatures—to bloom properly. If, after a few years, the plant stops growing or blooming, it may be time to repot it into a larger container with fresh soil.
What to Do If Your Hydrangea Becomes Pot-Bound
If a hydrangea (or any plant) stays in its container too long, it can become pot-bound—when the roots start circling the inside of the pot. While not a big issue at first, it can become harmful over time. Fortunately, it’s easy to fix.
When repotting a pot-bound hydrangea, choose a new pot that is 2 to 4 inches larger in diameter than the original pot. After removing the plant from the original pot, “Loosen the roots up and spread them out by scoring with a knife or gently separating with your fingers before repotting,” says Peter Kruger, director of Global Product Sourcing & Development for Ball Horticulture. “It may seem harsh, but it actually promotes more root growth to help the plant get established.”
Additional Tips for Growing Hydrangeas
- Soil: Hydrangeas grow best in humus-rich soil. If your soil has a high clay content, amend it with compost and organic matter before planting.
- Watering: Newly planted hydrangeas need frequent watering to get established. Continue watering regularly for the first year or two. Once established, hydrangeas prefer consistently moist soil during the growing season.
- Fertilizer: Apply fertilizer in early spring. Bigleaf and Smooth hydrangeas may also benefit from a second application in midsummer.
- Pruning: Hydrangeas need to be pruned for maximum blooms, but the timing depends on the variety. Visit our How to Grow Outstanding Hydrangeas: A Guide for pruning tips and more care instructions.
Planting Hydrangeas in Summer? Avoid These 5 Mistakes
As we’ve established, summer isn’t the ideal time to plant hydrangeas, but if you have your heart set on bringing one home, avoiding these common mistakes can make the difference between a shrub that thrives and one that struggles.
1. Don’t Planting During the Hottest Part of the Day
Midday heat puts extra stress on a newly planted hydrangea before its roots have had a chance to establish. If possible, wait until early morning or evening when temperatures are cooler and the sun is less intense. That gives the plant several hours to settle in before facing the day’s heat.
2. Don’t Choose a Spot with Too Much Afternoon Sun
Many hydrangeas appreciate morning sun but benefit from protection during the hottest part of the afternoon, particularly in warmer parts of the country. A location with dappled shade or afternoon shade helps reduce wilting and keeps blooms looking fresher longer.
3. Don’t Forget to Mulch
A two- to three-inch layer of organic mulch around the base of the plant helps conserve moisture, keeps the soil cooler, and reduces weed competition. Just be sure to keep the mulch a few inches away from the stems to prevent excess moisture from collecting against the plant.
4. Don’t Assume Rainfall Is Enough
Summer thunderstorms often wet only the soil’s surface. Newly planted hydrangeas need slow, deep watering so moisture reaches the entire root ball. After a rain, check the soil with your finger or rain gauge before deciding to skip watering.
5. Don’t Fertilize Right Away
Newly transplanted shrubs are focused on establishing their root systems, and fertilizing too soon can encourage tender new growth before the plant is ready to support it. Excessive amounts of synthetic fertilizer can also damage young roots. If your hydrangea came from a nursery, it may already be growing in a potting mix that contains slow-release fertilizer. Wait until the shrub has had time to establish before fertilizing, and always follow the label directions for the product you choose.
Planting in a container now lets you enjoy the blooms this summer without putting the shrub through the stress of establishing in hot garden soil. Once cooler weather arrives in fall, you can move it into the landscape where it will have the best chance to thrive for years to come.
