Why are peonies so charming? Is it because of their large traditional blossoms that take you back to an idyllic past? Or because they are great for bouquets? Their lush and large foliage? Their delicate colors in shades of white, pink, coral or burgundy? Whichever the reason, if you want a really abundant floral display this year, they need some tender loving care as soon as the first shoots appear.
To be honest with you, peonies hardly ever disappoint once they are adults and established (they won’t bloom for the first two years – so don’t worry). This is, as long as you plant them in a sunny position, feed them well, water them and preferably mulch them.
Everybody knows these things, but there are some actual tricks of the trade I want to share with you.
When spring comes, and you see the first shoots of herbaceous peonies come out of the ground, it is time to start thinking about them, and I have 5 tips (or tasks) for you to make sure that they will give you the biggest and most abundant blooms ever!
Let’s start then!
Mind the Shoots!
The shoots of herbaceous peonies are already a spectacle in themselves! Their purplish-reddish color, the tender appearance, these flowers already start charming you early in spring…
Of course, the early shoots look strong and vigorous, don’t they? And they are, but… This is time to start looking after them and at different stages.
As soon as the shoots appear, remove mulch or fallen leaves, debris etc. around them. They need to grow freely and without risking infections.
Spring is usually a rainy time of the year (or late winter if you live in a hot climate). And yes, there are some diseases that can affect them, especially when the shoots are young. So, beware of Botrytis Blight (Gray Mold)!
Look out for young shoots that appear to suddenly “wilt” and fall over at the soil line, or stems with dark, water-soaked, slightly sunken areas called “cankers”! If you do, cut off the affected ones immediately, sterilize your tools and then spray all the healthy ones with a solution of water, neem oil and liquid soap (one or two teaspoons and a squeeze of soap per liter of water).
Phew! So, we got through the fungus problem (quite common in damp springs) – but it’s not over yet.
You see, the problem is that peonies tend to “overate their strength”. How many did the charming lady produce at first? The chances are that they are far too many. But wait…
Yes, wait till they produce the first few leaves, or when they are about 6 inches tall (15 cm), and then keep the 5 to 7 strongest ones and cut the others down at soil level.
Feed Early (But Don’t Overdo Nitrogen!)
Now, I know what you’re thinking. “Feed them? Of course I feed them!” But here’s the thing – peonies are already incredible at pushing out foliage. Give them too much nitrogen and you’ll end up with a gorgeous bush of leaves and barely a bud in sight. Trust me, I’ve seen it happen, and it’s heartbreaking when July rolls around and your neighbors are cutting bouquets while you’re staring at a shrub.
So what should you do instead? As soon as those first shoots break through, give them a balanced meal, but keep the nitrogen modest. I reach for a fertilizer with a higher middle number – think 5-10-5 or something similar where phosphorus takes the lead. That middle number is what coaxes the roots into building strong stems and, more importantly, stuffing those buds with all the energy they need to open wide and proud.
A light handful around each plant, scratched gently into the soil and watered in well, is plenty. Don’t go piling it on. Peonies aren’t greedy feeders; they’re old-fashioned flowers with old-fashioned manners. A modest spring breakfast is all they ask for. If your soil is already decent, you might even get away with a top dressing of well-rotted compost instead of commercial feed. Just keep that nitrogen low, and let the phosphorus do the talking.
It’s a Matter of Depth…
Yes, you are right, I’m being cryptic… I mean that it’s a matter of planting depth. “But when I planted them, it was all right,” you may say. True, but what happened afterwards?
Winters can erode the soil with heavy rains, frosts and windy weather, and the roots may surface again. This is especially dangerous to younger peonies. The result? Weaker plants.
On the contrary, if soil has accumulated, you have another problem; your peonies will still produce lots of leaves, but few flowers.
So, stick your finger in the soil and check that the roots start 1 to 2 inches deep (2.5 to 5.0 cm). Be careful not to damage the shoots.
If they are too deep, gently remove some soil – I use my hands to be gentle with the shoots.
If they are too surface, add some rich soil on top…
Install Supports as Early as Possible!
Peonies have lush leaves and they are bushy – so, imagine the mess for you and risk for them if you install support later?
And what’s the best support? Most gardeners would suggest peony rings, A.K.A. peony cages, and I agree. They come in different shapes now, some even artistic, but I find that some of those can give you more trouble than benefits.
Choose simple round rings with legs to stick in the soil – they are very cheap an you can find them online very easily.
“How about individual stakes,” you may ask? Well, they are possible, but more fiddly; then you will need to tie each stem to a support…
Finally, I was forgetting… Install the support when the peony stems are about 6 to 8 inches tall (15 to 20 cm).
Are You Sure You Are Watering Your Peonies Correctly?
Of course, we all know that plants must be watered, but how to do it correctly? I have a little “secret” to share with you, and this is especially important for younger peonies, but good for adult ones as well.
You see your peonies growing fast overground in spring, don’t you? But how about underground? Well, it’s the same.
This is when the roots of peonies (and many other plants) grow the fastest!
“And what’s it got to do with watering?” Your peonies’ roots are looking for two things, food and water. And if they find everything they need at surface level, guess where they will grow?
Deep water your peonies especially in spring. The water must penetrate at least 8 to 10 inches into the soil (20 to 25 cm). This means a couple of inches of surface water.
What’s very important is that you only water peonies a lot but once a week, and only if the soil is dry – otherwise you will be training their roots to stay at surface level.
Sorry, I Can’t Resist!
To conclude this little article, I want to leave you with a final tip – and it is linked to watering. Most people know to feed peonies super early (don’t use a high nitrogen fertilizer, they have no issues producing leaves…), mulch etc., but they forget one thing…
Improve drainage with 1 inch (2.5 cm) of coarse gardening sand (or gypsum if your soil is heavy clay) – that will help you deep watering them, but at the same time avoid any rot!
Written By
Amber Noyes
Amber Noyes was born and raised in a suburban California town, San Mateo. She holds a master’s degree in horticulture from the University of California as well as a BS in Biology from the University of San Francisco. With experience working on an organic farm, water conservation research, farmers’ markets, and plant nursery, she understands what makes plants thrive and how we can better understand the connection between microclimate and plant health. When she’s not on the land, Amber loves informing people of new ideas/things related to gardening, especially organic gardening, houseplants, and growing plants in a small space.