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Botrytis infected peony stem and bud

An ugly name for and ugly disease!

Botrytis or gray mold is a fungal disease that attacks many perennials but especially peonies – the “aristocrat” of the spring perennial garden!

A peony bud and stem infected with botrytis

A peony bud and stem infected
with botrytis

Anyone who grows peonies eagerly anticipates the appearance of their glorious blooms in mid to late May. Sometimes we are bitterly disappointed when our peony stems suddenly begin to turn brown, wilt, and flop over.

It is especially upsetting when this occurs after the flower buds have developed and are beginning to swell on the stems. We can hardly wait for them to open and reveal their beautiful flowers – but then … Ugh!

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Botrytis at the base of this peony leaf

Botrytis at the base of this peony leaf

Botrytis blight often rears its ugly head in the garden after late spring freezes or during periods of cool, rainy weather. It can be especially damaging to plants when wet, humid conditions persist over several days.

Botrytis (Botrytis paeoniae) is probably the most common disease of herbaceous peonies. It typically first appears as brown or black patches on the bases of the young leaves and stems when they emerge in the spring. The stems and leaves wilt rather quickly and fall over.

This peony bud would have produced a beautiful flower!

This peony bud would have produced
a beautiful flower!

A gray mold which produces and disseminates a tremendous number of spores eventually develops in these areas. These botrytis spores are carried by the wind and also by insects to the leaves and flower buds of other nearby peonies where they grow and cause leaf blight and bud rot. Often, this is when the damage becomes most noticeable. The very tiny flower buds turn black and fail to develop further while larger buds and the stems just below them turn brown and quickly droop over. Unfortunately, under favorable conditions, botrytis can quickly spread through your peony beds unless steps are taken to control it.

What can you do?

Botrytis spores beginning to cover this diseased bud.

Botrytis spores beginning to
cover this diseased bud.

If you notice botrytis on the buds, leaves, or stems of your peonies, carefully remove the infected plant tissue, place it in a bag and discard it in your trash – do not put it in your compost pile! Never prune infected stems and foliage while the plant is wet or you risk spreading the disease to other healthy plants.

Botrytis overwinters in dead leaves and other plant tissue so it is important to remove all plant debris from the garden in the fall. Cut peony foliage to the ground in September or October, bag it up, and put it in the trash. Rake up dropped leaves and remove them from the garden.

Again, do not compost any of this plant debris.

Leaf blight caused by botrytis often develops after the blooming period.

Leaf blight caused by botrytis often
develops after the blooming period.

In the spring, just as the shoots begin to come up, spray the shoots and the surrounding soil with a mixture of Bonide Mancozeb (with Zinc) and Immunox according to the label directions. Then begin a spray program, spraying first with Mancozeb, copper fungicide, or Bonide Fung-onil and then 10 days later spray with Immunox or one of the other fungicides that you didn’t use for the first spray. Repeat this every 10 days until they flower.

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In our gardens, botrytis wasn’t too bad this year. However, I have had a few calls about the sudden death of peony buds or the lack of bud development all together. If you don’t see signs of botrytis, the following are a few other reasons why peonies might fail to bloom:

  1. A late spring frost or freeze might kill the buds. We had some very cold nighttime temperatures this spring. It dropped into the mid 20’s several times in the middle of April and we even had frost in mid May this year.
  2. Peonies may be planted in too much shade. Sometimes, as your landscape matures, full sun gardens can become more and more shaded. Peonies will bloom in bright shade but the bloom will begin to decline in deeper shade.
  3. Too much nitrogen will hinder flower development. Your grass loves lots of nitrogen; peonies, not so much. Nitrogen promotes lush green growth – just what you want for your lawn but not your perennials. Foliage comes at the expense of flowers. Be very careful to keep your high nitrogen lawn fertilizer out of your perennial beds if you want a nice show of flowers! Choose an organic fertilizer like one of the Espoma “tones” or another fertilizer that is lower in nitrogen.
  4. Bare root peony showing the two types of "eyes".

    Bare root peony showing
    the “eyes”.

    Your peony may be getting too old. As your peonies get age, flowering may slow down. To rejuvenate your peonies and make them bloom well again, dig and divide them in September or October when the foliage begins to turn brown. Here are some tips.

  5. Peonies are planted too deeply. Plant your peonies so the eyes are no deeper than 2″ below the soil surface. If they are planted deeper than this, they may not bloom.

Our peonies were pretty spectacular this year! I hope yours were, too!

Peony 'Gay Paree' blooms in the Viette gardens. It is one of Andre's favorites.

Peony ‘Gay Paree’ blooms in the Viette gardens. It is one of Andre’s favorites.

If you don’t have any planted in your garden, maybe it’s time to find a sunny spot for one or two! Check out our list!

Until next time – Happy Gardening!

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Helleborus orientalis begin blooming in mid to late winter.

On Groundhog Day, ‘Punxsutawney Phil’ predicted a speedy end to winter and we were all eagerly anticipating an early spring.

This morning wet snow and sleet lay on the ground

This morning wet sleet
lay on the ground

At the time, it seemed like he might be spot on but less than a week later came the big New England blizzard that dumped up to 3 feet of snow from northern New Jersey to Maine with Boston getting clobbered with the brunt of the storm. Since then we have had two major March snow storms here in the Shenandoah Valley and believe it or not, a winter weather advisory for snow and sleet came across my computer yesterday afternoon and by 6:45 pm it was snowing like crazy!

Oh for Pete’s sake – what do groundhogs know anyway! All they do in my yard is dig in my garden, eat my vegetables, and cause me a big headache!

Quince buds

Quince buds

Yesterday morning, I took a walk through the Viette gardens to see if I could find some signs of spring. It was quite cold and pretty cloudy – not at all spring-like! The gardens are all cleaned up and ready, but spring is still holding out. Of course many of the daffodils and a few of the other spring bulbs are up and blooming beautifully and I can tell spring isn’t too far off because the buds on many of the trees and shrubs are quite swollen and many are beginning to show the tiniest bit of color.

Forsythia just beginning to pop.

Forsythia is just beginning to pop.

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A few bright yellow flowers have popped open on the forsythia but most of the buds are still pretty tight. The buds on the flowering quince are nice and plump, just waiting for a warm April day to push them along. I have a feeling that all it’s going to take is a few warm, sunny days and spring will be bursting forth in a gush of blooms!

Mahonia repens

Mahonia repens

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A striking plant in the garden at this time of year is the low-growing Mahonia repens. Its deep burgundy winter foliage makes a gorgeous backdrop for the bright clusters of chartreuse flower buds. Later in April, these buds will open into racemes of beautiful deep yellow flowers and the holly-like evergreen foliage will gradually develop its deep blue-green summer color.

A beautiful black hellebore

A beautiful black hellebore

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The Viettes have a wonderful diversity of Helleborus planted throughout the gardens including some very unique new cultivars. These are all in full bloom and have actually been blooming for several months. They are truly one of the first flowers of the season!

The herbaceous peonies in the gardens are just beginning to poke up through the ground, though the ones growing in more exposed areas are not up as high as those that are more protected.

Just a reminder – if you had problems with botrytis blight last year, now is the time to spray these newly emerging peonies with the first round of a fungicide like Mancozeb or liquid copper according to the label directions.

Tree peony buds and young foliage

Tree peony buds and young foliage

The tree peonies are also beginning to break dormancy and their new foliage has a lovely pinkish-red tint. These miniature stems and leaves were enveloping the swelling flower buds and created a very interesting pattern when observed up close –
subtle beauty in the garden can be found everywhere!

Tree peonies are my favorite type of peony. I just love how they look in the garden with their giant crepe paper blooms covering the tall shrub-like plant. Cultivars bearing single, semi-double, or double blooms can be found in a wide variety of colors and many even have a lovely fragrance. Tree peonies often begin blooming in early May, several weeks earlier than the herbaceous peonies, and because they have woody stems, they don’t usually fall over from the weight of the flowers. Spectacular!

Intersectional or Itoh peony

Intersectional or Itoh peony

Andre’s yellow intersectional peony (a.k.a. Itoh peony) ‘Bartzella’ has loads of nice fat buds on it. This interesting new peony type, which is a cross between an herbaceous peony and a tree peony, combines many of the best traits of each of its parents. It produces multitudes of large, crepe-like blooms on strong stems that hold up in the wind and rain, yet it dies back to the ground and gets cut back in the fall like the herbaceous peonies. The foliage is similar to tree peony foliage and remains attractive through the fall. A very nice plant and worth having in the garden, though they sell out fast in the spring!

Lamium maculatum

Lamium maculatum

Some of the early blooming perennials are just peeking up and some even have a few blooms popping out already. The Lamium maculatum which has made a wonderful ground cover around a small water garden is blooming quite nicely although its foliage hasn’t completely filled out yet. I also discovered a beautiful Pulmonaria that had pushed up a few short flower scapes even though its foliage was just beginning to emerge.

Spring IS coming – don’t you worry! My fear is that it will come and go too quickly. Spring is one of my favorite seasons and I really hope that when it finally does arrive, it stays for a while!

Until next time – Happy Spring!

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