Do you want a lush hydrangea bush bursting with giant, colorful blooms this summer? If you’ve ever felt a twinge of envy walking past a neighbor’s prolific hydrangeas, this is the year to turn the tables. The secret to those show-stopping round pom pom hydrangea flowers isn’t just good luck—it’s all about what you do in the spring.
With a few smart steps now, you can set your hydrangeas up for success. Here’s what to do this spring to grow those giant, gorgeous hydrangea blooms you’ve been wishing for.
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Prune Correctly
First things first: proper pruning is key—but only if your hydrangeas actually need it. One of the biggest mistakes you can make is pruning too much. Not all hydrangeas benefit from a trim, and cutting back the wrong variety can mean no blooms come summer.
In fact, pruning them too much can remove the very stems that would’ve produced flowers. Trust me—I learned this the hard way. I once pruned my bigleaf hydrangeas in early spring, not realizing they bloom on old wood, and they didn’t produce a single flower that summer.
Some hydrangeas bloom on old wood, which is last year’s growth. Bigleaf and oakleaf hydrangeas fall into this category, and they don’t need regular pruning.
If you’re unsure, it’s safest to skip the pruning altogether or just lightly clean up any dead or damaged stems.
Other types, like panicle and smooth hydrangeas, bloom on new wood, which means the growth that appears this season. These varieties actually benefit from a good early spring trim. Cutting them back encourages stronger stems, fuller shapes, and bigger, better blooms.
If you’re not sure which type you have, try to observe where the blooms appear—on older, woody stems or on fresh new shoots. When in doubt, play it safe and don’t prune. A cautious approach is better than accidentally snipping away your summer display.
Fertilize in the Spring
Feeding your hydrangeas in the spring can make a big difference when it comes to bloom size and overall plant health. Start the season off right by applying a slow-release, balanced fertilizer in early spring. Look for one with a balanced ratio like 10-10-10 or 14-14-14.
Be careful to avoid fertilizers high in nitrogen—they’ll encourage lush, leafy growth at the expense of flowers. Fertilizer labels list three numbers (like 10-10-10), representing the percentages of nitrogen (N), phosphorus (P), and potassium (K)—so if the first number is much higher than the others, it’s high in nitrogen.
If you’ve ever wondered why your hydrangea looks healthy but won’t bloom, too much nitrogen could be the culprit. The right fertilizer gives your plant the boost it needs to produce those big, beautiful blooms you’re aiming for.
Water Your Hydrangeas
After a long winter dormancy, hydrangeas appreciate a deep, refreshing drink. As the soil begins to warm in spring, give your plants a thorough, slow watering to help reawaken their roots and kickstart healthy growth.
Deep watering encourages the development of strong, deep root systems, which in turn support bigger, more resilient blooms throughout the season. Aim to keep the soil consistently moist but not waterlogged, especially during dry spells—hydrated roots are happy roots, and happy roots mean show-stopping flowers.
Trim Tree Branches
Hydrangeas can tolerate some shade, but that doesn’t mean they don’t need sun—especially if you’re aiming for big, beautiful blooms. If your plant isn’t getting enough sunlight, it won’t flower as prolifically. Ideally, hydrangeas thrive with morning sun and afternoon shade.
One easy way to get more light to your plant is to improve sunlight exposure by trimming back nearby trees or overhanging branches. A little extra light can make a big difference in encouraging more prolific blooms.
Transplant Hydrangeas (If You Have To)
Sometimes, trimming back tree branches isn’t enough to improve sunlight exposure for your hydrangea—especially if it’s planted in deep shade. On the other hand, your hydrangea might be exposed to too much sunlight, sitting in intense, full sun all day. If you’re facing either of these issues, it may be time to transplant your hydrangea to a more suitable location, ideally one with morning sun and afternoon shade.
Spring is the best time to transplant hydrangeas, just before new growth begins. After moving your plant, be sure to water it thoroughly to help it settle into its new spot.
Keep in mind that transplanting requires ongoing commitment. Since your hydrangea’s roots are not yet established, you will need consistent watering throughout spring and summer to establish healthy roots.
It’s not a low-maintenance task, so only transplant if you’re prepared for the extra care—this means not taking extended vacations during the summer unless you can arrange for someone to water your hydrangeas while you’re away!
Mulch
Mulching in spring is a simple step that delivers big rewards all summer long. A 2- to 3-inch layer of mulch helps retain soil moisture, regulate temperature, suppress weeds, and even improve soil quality as it breaks down.
Choose organic mulches like shredded bark, compost, or leaf mulch—these not only insulate the soil but also provide a slow, steady stream of nutrients. Think of it as giving your hydrangeas a cozy blanket and a long-lasting buffet, all in one.
Adjust the Soil PH
Spring is the perfect time to adjust your soil’s pH—especially if you’re hoping to influence the color of your bigleaf hydrangea blooms. These hydrangeas are unique in that their flower color can shift based on the soil’s chemistry.
For vibrant blue blooms, you’ll want to lower the pH by adding aluminum sulfate or elemental sulfur. I use this soil acidifier to turn my hydrangeas blue.
If you want pink flowers, raise the pH with garden lime. I use this garden lime to turn my hydrangeas pink.
If you’re aiming for purple blooms, the goal is to land somewhere in the middle—a more neutral pH, typically around 5.5 to 6.5.
Achieving that balance can take a bit of trial and error, but blending small amounts of both acidifying and alkalizing agents (or simply allowing your soil to hover naturally in that mid-range) can encourage that rich lavender or violet tone.
Since these changes take time to work their way through the soil and into the plant, the earlier you start in the season, the better your chances of seeing vibrant results by summer.
Some Things Are Out of Your Control
Even if you follow every tip on this video perfectly—feeding, pruning, watering, and positioning your hydrangeas just right—there’s one important thing to understand: sometimes, nature has the final say. No matter how much effort you put into your garden, there are certain factors you simply can’t control, and the weather is a big one.
The ideal weather is a gradual, steady spring warm-up with no surprise frosts, mild summer temperatures, and regular rainfall. When all those elements fall into place, you’ll likely get big, full, vibrant blooms that stop people in their tracks. The results can be spectacular.
However, with climate change, we are experiencing greater weather fluctuations, and hydrangeas are sensitive to unpredictable weather swings.
A few years ago in Connecticut, we had the worst year. It was an unusually warm start to spring. My hydrangeas started budding early, and it looked like we were headed for a fantastic bloom. But then, out of nowhere, a hard freeze hit. Those tender buds couldn’t handle the cold snap, and most of them were lost.
That year, not only did my hydrangeas barely bloom, but all my neighbors had the same issue. It was a town wide disappointment- we all had anemic hydrangea plants with barely any flowers!
Compare that with another year when everything lined up perfectly. We had a gradual spring warm-up, steady rainfall, and no unexpected frosts. The results? Hydrangeas were blooming everywhere—even the ones growing wild by the roadside that no one tends to. The flowers were full, colorful, and absolutely stunning.
So while there’s a lot you can do to encourage big, beautiful hydrangea blooms, don’t be discouraged if Mother Nature has other plans. Gardening always involves a little bit of faith, flexibility, and appreciation for the seasons.
And remember—if your hydrangeas don’t put on a show this year, there’s always next year. That’s the beauty of gardening: every season brings a new chance to grow.