How I Love to Hate You
There is no plant here at Natchez Glen that I have a more complicated relationship with than Paeonia. I love that moment in spring where their goblet-shaped flowers develop and grab attention from all the other plants. I hate when that moment is over. And in warm climates it can, in fact, be only a moment. They do very little the rest of the year. So the question becomes, is it worth it? The answer is yes, no, and it depends.
In a warm region of the world, growing peonies alone not planted in gardens seems like a very boring choice. Your peony will bloom maybe as early as late April and finish blooming by the first or second week in May, and you're left with a rather lifeless area. As the season progresses, the foliage will start to deteriorate, and by September, it will look down right bad. The highest highs and the lowest lows are how peonies perform in warm climate gardens. Is there any way to change this version of gardening future? Yes. It is adding lots of other plants to support the shortcomings of Peonies.
In more mild or cooler climate regions, Peonies will have bigger flowers, and their foliage will hold up through the season. In areas like the Pacific Northwest, the foliage of Peonies is even used in floral design work late in the year as they develop fall color tones. Still even in these more moderate climates, peonies planted by themselves are a lonely plant and live their best life when surrounded by friends.
Paeonia lactiflora is the species parent of most of the peonies we grow in gardens. These are herbaceous peonies or sometimes called "garden peonies," a rather poor choice of words because all peonies belong in gardens. The name would imply that the origins of the Peonies we grow today from Paeonia lactiflora would have a more delicate garden start, but that is not the case. Despite the flowers giving an appearance of delicate, Paeonia lactiflora natively grows at elevations starting at 5000 feet or more. Their native range is from Western China, Siberia, and Mongolia. Why do these places of origin matter for the beloved peony? Those origins tell us a lot about who they are. In the those areas, the average summertime highs are very mild, averaging only 70 degrees which is what explains this contrast between warm climate and cool climate performance.
Peonies having evolved in these cool climates need chill time. The cool hours of winter and the cool nights in summer allow them to produce large flowers as well as keeping their foliage less stressed. Think of the anatomy of a peony tuber as a battery, and cool weather as the time it gets to rest. In warm climates, a peony is asked to run fast and hot. It will result in flowers, but a lot of the peonies energy is being used to keep up with the heat via transpiration. The result is flowers but smaller flower sizes and sometimes fewer flowers. In cool climates, the peony is only asked to slowly awake from its winter slumber and to begin to focus energy on flowers and only flowers. The result is a larger more "wow factor" flower in size similar to what we see in the cut flower world from the Peonies being grown in Alaska.
So is all hope lost for those that grow peonies in warmer climates? Remember how we started this by saying my relationship with peonies is complicated? I grow nearly 200 peonies here at Natchez Glen. Despite me being intimately aware I am not able to grow the same quality of peony as in cooler climates, I really don't care. I'm not growing peonies to win any flower size contest. I grow peonies for that moment in spring where they take my breath away if even for a moment.
Herbaceous peonies have also seen much change from their time with only Paeonia lactiflora parentage in the 1800s. There are now hybrids of herbaceous and tree peonies called either Itoh or intersectional peonies, which I think need to be trialed in a much more comprehensive way to see their heat tolerance. There are tree peony species, Paeonia rockii, that I have seen doing very well even in areas like coastal central California. So as much as we love peonies, we really haven't explored them maybe as much as we should have.
One of the main reasons for that is peonies are slow. Growing peonies from seed can take up to two years just to see the seed germinate and sometimes nearly six years before you see one flower. Because of this the industry of plants has mostly only shown us the older introductions, Sarah Bernhardt, Karl Rosenfield, and Festiva Maxima -- a pink, a magenta ,and a white peony -- that's all you need, right? Most of these peonies are produced from root divisions, and even tissue culture is being experimented with now on peonies.
Beyond our awareness of all of the species of peonies (link for more info on Paeonia Species) and where they come from, there is also the role of incredible breeding that has created so many exquisite varieties. Now we have peonies that bloom early, mid, and late. Some are large doubles and others that have an anemone form, far better than the mundane choices of pink, red, or white. Many of the introductions have also seen practical improvements like stem strength and the plants blooming earlier in life.
Yada, yada, yada -- this is all great, but my peony I bought at the big box store isn't blooming? First, shame on you for buying one at a big box store when you could have bought peonies from me. Second, there are two main reason peonies don't bloom: too much shade and planted too deep. Peonies, in particular standard herbaceous, need sun to produce flowers. Even in warm climates, a peony needs eight hours or more of sun to produce its blooms. In cool climates, herbaceous peonies should be planted with their eyes 2" below the soil line, and in warm climates, an inch below the soil line. Plant too deeply and you get foliage and no flowers. In rare cases, peonies will not flower because of heavy amounts of nitrogen in the soil.
That's all great, but in my case, I did all that right, and my peony is still not blooming. What cultivated variety do you have? The answer to that question would also tell a lot of the story. Remember some peonies bloom earlier in life than others, true late bloomers.
Got it, but my peony still isn't blooming. The other case where peonies will not flower is if they have been moved within the last two years. Peonies have very fine feeder roots that feed their tubers, and if those are lost in a move, the plant may not have enough energy to produce flowers over the next two years.
Ok, but my peony is still not flowering? If you cut back the foliage on peonies before it starts to yellow or in the winter you may not be allowing the plant to use its leaves as solar panels and recharge its' batteries to produce flowers the next year. Also, never attempt to pull off old foliage on peonies as many times the stems are near next year's eyes, and they can be pulled away as well. Always cut the foliage. I wait until late winter.
I didn't pull anything off, but my peonies are still not blooming. That's because your husband ran over them with a lawnmower every year for the last five years, and they are on strike.
Peonies are a strong plant that can grow happily in the same spot for decades. Some years they will produce flowers that will captivate and romance you. Other years the flowers will be smaller and fewer and you may feel cheated on. Either way the relationship with peonies will always be a complicated one.