Caring for Potted Hydrangeas
Walk into any big box hardware store, grocery store, or florist right now and you’ll likely run smack into a huge display of stunning pink and blue hydrangeas. As winter drags to a close, they’re a very welcome sign of spring. They make a wonderful gift for Easter or just about any spring celebration.
I was fortunate to be gifted with this beautiful pink hydrangea by a friend last week:
Gorgeous, isn’t it? The tag tells me that the variety is named Pink Sensation. I expect there was likely a blue flowered version sold alongside it.
Few other houseplants have as much colour and impact, which is why hydrangeas like these are so popular. In fact, they’re so popular that last week the social media gardening groups I participate in were full of questions about these hydrangeas! I decided to answer a few of the most common questions about pink and blue hydrangeas here:
How do I take care of a hydrangea?
These hydrangeas like bright light and thorough waterings, as needed. By that, I mean water them well (to the point that they’re soaked all the way through), but do not leave their roots to sit in a puddle of water—they want to drink, not float. This way of watering is better for the plant than giving it a little bit of water every day. But, hydrangeas are very thirsty plants—you need to check them every day, to see if they need to be watered thoroughly again. While they may look like a nice houseplant, they’re actually a shrub in a small pot.
Look at all of the growth on the plant (sturdy stems, thick leaves, big flowers) compared to the small rootball:
The flower petals will start to wilt/curl when the plant gets dry. Ideally, you would water it before the plant sends you that signal, but if you see the wilt/curl water it right away. I confess that I had forgotten just how thirsty these plants are (it’s been a few years since I’ve had one) and saw the poor thing shriveling before my eyes. I watered it soon enough to save it, but you’ll see that the edges of the leaves browned, and that’s not going to go away.
This is something to keep in mind if you see some on discount at your local hardware store (I saw two full racks of them at less than half price at a big box hardware store this morning—all of them with severely wilted petals. They were salvageable, but there would be some residual damage).
Can I plant my hydrangea outside?
Well, the answer depends on where you live. These are what are known as florist hydrangeas—they’ve been coddled and coaxed in a warm greenhouse in order to be in full bloom at your local hardware store in mid-March. They are primarily intended to be enjoyed as houseplants and then discarded, much like cut flowers (although they last a lot longer than cut flowers, and at a similar price point—a good thrifty choice!)
However, these hydrangeas can be planted outdoors and enjoyed for years to come a) if you live in the right climate and b) you care for them appropriately. There are many types of hydrangeas with varying degrees of winter hardiness. Most of the florist hydrangeas are from the Hydrangea macrophylla family—the best information I can find online says that they’re hardy in USDA zones 5 to 8.
If you live within those zones (or in a bordering zone and want to try your luck), once the weather has warmed up past any danger of frost, you can begin to slowly adjust the plant to outdoor temperatures and direct sunlight, moving it first to a shady and sheltered spot and then gradually transitioning it to a more exposed position. Once it has been acclimatized you can plant it in a lightly shaded to full sun location and keep it well watered until the roots are established. Next year, you can prune it in spring (as it flowers on new wood). Be advised that this is a shrub—in the right conditions it grows to be about 1 metre (3 feet) wide and high. Situate it accordingly.
Will my hydrangea stay pink/blue?
Many florist hydrangeas can be either pink or blue–the acidity of the soil (the “soil pH”) determines whether the flowers will be pink or blue. You might notice that the flowers start out green when young:
It’s quite a fascinating phenomenon you can read more about here if you’re interested. In essence, soil with a pH level at or below 5.5 will produce blue flowers, soil with higher pH levels will produce pink flowers. If you’re just keeping your hydrangea indoors to enjoy as a houseplant for a season you don’t really need to worry about this–the soil pH is the plant pot is not going to change in a few weeks. But if you’re planting it outside you could add sulfur* or aluminum sulfate* to your soil in order to maintain blue flowers (follow the instructions on the package).
These are the top questions I’ve been seeing about these potted hydrangeas. If you have one, I hope my tips help you care for and enjoy it! And if you have a question about florist hydrangeas that I haven’t covered please leave it in the comments below and I’ll try to find you an answer.
*Disclosure: some of the links on this page are Amazon affiliate links, meaning, at no additional cost to you, I will earn a commission if you click through and make a purchase.
What is the best fertilizer if grown outdoors?
Hydrangeas are heavy feeders, a lot like roses, so fertilizing them is a good idea. Any fertilizer you’d use for roses would likely be good.
I have potted hydrangeas on a veranda facing south. When do I need to prune them? How vigorously?
Most hydrangeas get pruned in the spring. Although there are some varieties that bloom on old wood (i.e. they set their blooms the year prior–if you prune that kind in the spring you’ll cut their buds off). It’s hard to provide advice without knowing exactly which hydrangeas they are. As to how much to prune–my plants are large shrubs and I usually prune them about 18″ off the ground.
I have the large leaf Hydrangeas which were not getting blooms. Then I researched and found out that the old wood I was pruning in the Spring had the bloom buds on them. Some had died due to the very cold weather we can have at times living in central Illinois. So last fall I covered them with leaves and this spring the buds on the old wood survived. I’m hoping and looking forward to having flowers this year. So if you have the large leaf Hydrangea do not prune them in Fall and if you live in a climate that the temps drop below the 30-20F cover the plants in the winter to prevent the old wood with bloom buds from dying. Your reward should be beautiful flowers.
Hello! I know you said that as house plants they will last for a few weeks. Does that mean they’ll ultimately die if I dont acclimate them outdoors? Or would it be possible to keep them indefinitely as house shrubs. Lol. I do have Pink Sensations, so they very plant your helpful article spoke about!
Hi Kenne, hydrangeas need a dormant period, so you’d have to put them in a very cold place (an outdoor porch?) for that period, during which time they’d lose all their leaves and not look very good. Additionally, they are shrubs (i.e. small trees) so that means they will form a sizeable root ball over time. If you wanted to keep them as houseplants they’d need eventually need a very large pot (which would need to be schlepped outside for their dormant period, and then back in again.) I know they’re beautiful plants when they’re in bloom but in my opinion it’s too much work to try to keep them as houseplants. I recommend enjoying them for the season, composting them and buying a fresh one the next spring.
Okie dokey! Thanks so much for the help, Jennifer! I really appreciate it! I have no idea what I’m doing so your blog has really helped me out a lot.
I have had good luck wintering over shrubs. So I’ll probably try this because I also have a pink sensation. When you say put it in a very cold spot what do you mean?
I’d love to hear how it goes! When I say very cold I’m thinking freezing temperatures or as close to it as you can get in your area. You want it to go into dormancy. If you live somewhere that has real winters you could put it outside in a protected area, but I think it would be wise to insulate the pot first to help protect the roots (I’ve heard of people doing this with bubble wrap, but styrofoam is also an option). Good luck!
I bought this plant this year, it has 2 flowers on it, is there any thing I can do to promote new buds
Hmm, probably not for this year, as I believe that they set all of their buds at once. If this is a plant you’re planning to keep to next year, you could promote new buds for next year by fertilizing it (hydrangeas are very heavy feeders)–I’d feed it a couple times this year and then every two weeks next spring from when new growth first appears. Fish emulsion fertilizer or a standard rose fertilizer would work.
Hello! My name is Sofia. I just bought today pink sensation at grocery store in 6 in pot and it has already 10 blooms. I would like to plant it in a larger pot to keep outside on the deck. I will be very appreciated if i will get some recommendation, such as: 1.What size the pot do i need now and do i need a larger pot next year? 2.How many holes to do for good drainage? 3. Is it OK to put mulch on the bottom? 4.Do i need to put some fertilizer during the planting or latter on,when? Any other recommendations? Thank you very much.Looking forward to plant this beauty and enjoy all summer.
I live in Las Vegas, NV and the weather is very dry and starting to get very hot right now (May 2021). I received these flowers as a Mother’s Day gift. Do these flowers/shrubs require direct sunlight, and should I put them outside or keep them indoors?