Hydrangea Mania

Writing by Leslie Dock

Artwork by Elizabeth Gourlay

*Editor’s note: Hydrangeas are so beloved in our area that Leslie Dock created a complete printable guide on what to buy and how to care for them. Click here to download your expert tips.

Igrew up in the Midwest—Milwaukee, Wisconsin, to be exact. The small suburban gang of kids I ran with trampled many a day lily and knew to avoid the spiny threat of the ever-present spruce tree, but nowhere in my memories do I recall a single hydrangea. 

The journals from my late teens and early twenties contain observations of landscapes, animals, plants, weather patterns and many drawings. However, it wasn’t until a trip to Cape Cod in 1999 that I first experienced the glory of what I now think of as New England’s favorite floral shrub.

Twenty-five years later, I am still wowed by the size, color and proliferation of a hydrangea’s blossoms. A lone specimen can really hold its own, brightening even the most drab corner of a yard. Plant two or more together and brace for impact. Multiple hydrangeas are not just a bunch of pretty shrubs with nice flowers; they are a floral event. It’s no wonder we see so many here in Westchester. 

Beauty is not the only reason for hydrangea celebration. They are easy to maintain and thrive in a variety of sun exposures. They are native to our region, come in a variety of shapes, sizes and colors, smell great, and many are a great source of food for bees. 

People who have hydrangeas love them and either want to learn how to care for them or want more. I get more questions about hydrangeas than any other non-edible plant. Here’s how you care for them, depending on your experience with both gardening and hydrangea obsession.

Just Getting Started: You are just entering the gardening arena and don’t know which hydrangeas to choose or where to place and prune them so they look their best.

Finding Your Way: Your small hydrangea collection is respectable. You want to know how to properly prune them and wonder just what you’ve got.

Talk of the Block: Walkers often stop to gape at your summer spectacle. You spend a little extra time outside each day just to admire those impossibly blue globes and delicate white explosions of petals. Still, you long for something more — variety, nuance, a bold choice with structure.

Just getting started

Welcome to the fun zone. Hydrangeas are a great shrub to start your gardening journey. They are pretty forgiving as long as you are mindful of the amount of sun and water they receive.

First, select the optimal spot for your hydrangeas. Ideal conditions are:

• Morning sun and afternoon shade.
• Hydrangeas require well-drained soil (avoid areas that flood).
• Soft ground.
• Fertile, weed-free soil. (Head to our website for tips on how to weed and prepare your soil.)

When it comes time to shop, native species like Hydrangea quercifolia (Oakleaf) and Hydrangea aborescens (Smooth) are best because they easily assimilate into our local ecosystem.

Oakleaf hydrangeas work best in areas with a good amount of sun, so you get a full display of blooms from spring through fall; their leaves change color from green to orange, then red and maroon. Prune them in the summer, after blossoms begin to fade. 

Smooth hydrangeas, also called Wild hydrangeas, grow best in full sun; just be sure to give them adequate water in the afternoon. They will produce large, showy blossoms and can tolerate heat and cold. Prune stems to the ground in late winter since this species blooms on new wood. 

Finding your way

Since you have some experience under your belt, it’s time to take a slightly deeper dive into all things hydrangea. A well-stocked nursery will carry up to seven species of hydrangea. 

The most common species sold in the U.S. is the Hydrangea macrophylla, known as Bigleaf and/or French hydrangea. The species contains Hydrangea macrophylla (Mophead), Hydrangea macrophylla v. normalis (Lacecap) and Hydrangea macrophylla v. serrata (Mountain). 

The variety you’ll see the most is Mophead. Just as the name denotes, the blossoms resemble a mop head: round and dense with sterile small flowers. They grow best in part shade, benefit from afternoon sun protection and thrive in our area. 

This species also includes the highly-coveted blue varieties. I have a friend who confessed to loving blue hydrangeas so much that she once crept onto private property to steal some blossoms. If you purchased a variety expecting blue flowers and have yet to see them, you needn’t resort to thievery. Instead, amend your soil with a soil acidifier, iron sulfate or compost so it’s more acidic. 

Lacecap has a lace-like appearance with closed, fertile center buds, surrounded by a ring of open, sterile blossoms. They provide food for bees and butterflies and are a nice choice for anyone looking to attract pollinators.

Mountain, named for their tolerance to cold, is the least common. They are built to withstand higher elevations and their accompanying colder climates. You might choose a mountain hydrangea for a particularly cold spot on your property with ample afternoon shade.

No discussion of macrophylla would be complete without a mention of Endless Summer hydrangeas, a special hybrid bred to re-bloom after deadheading. This means they typically blossom from spring through summer, 10-12 weeks. They bloom on old and new wood, so even if you forget to prune at summer’s end, you can prune in late winter or early spring and still get blooms. Endless Summer comes in both Mophead and Lacecap varieties, and there are lots of colors to choose from. If they don’t bloom at all for a season, it’s often due to a lack of nutrients or excessive heat, sun or shade. Some speculate that climate change may also be a factor. 

Talk of the block

Since you’ve already got it going on, how about a little challenge? You likely have plenty of Bigleaf and Smooth hydrangeas gracing your gardens, but have you delved into Climbing hydrangeas or pruned your Panicle hydrangeas into tree form?

Hydrangea paniculata (Panicle) is known for its large, cone-shaped flowers and tolerance to cold. They are the only hydrangea that can be pruned into tree form. Easily identified by their relatively narrow leaves that grow three to a whorl, Panicle hydrangeas are very forgiving when it comes to pruning. Since they bloom on new wood, they can be pruned back without fear of missing out on next season’s flowers. 

Blossom color is not determined by soil acidity, but it will remain longer if nighttime temperatures stay at 70 or below. I get this species as I tend to fade in the heat, too.

If you are really feeling creative, check out Hydrangea petiolaris (Climbing), which can climb 30-80 feet. Tiny suckers, called holdfasts, are this plant’s climbing secret. Climbing hydrangea boast massive, fragrant blooms if given enough sun, though they can handle more shade than other hydrangea species. They are bee and butterfly magnets. 

There is a lot of information in this article and even more online. There, you’ll also find a printable chart to help you keep it all straight. As you learn to identify the plants you already have, be sure to tag them so you know when to prune them. Other than that, remember that “the more the merrier” is always a good rule when it comes to hydrangeas. And don’t forget to be on the lookout for blossom thieves once your hydrangea game is strong.

This article was published in the March/April 2024 print edition of Connect to Northern Westchester.