In this newsletter you will find all information that is currently relevant to the crop of peonies. We trust that this information will help you in achieving a successful crop. Feel free to contact us for questions and remarks!

For a long time now you are receiving this newsletter from us. With information regarding the cultivation of peonies. Because we are always looking for ways to improve ourselves, we would like to hear from you how relevant this information actually is. What are things you would like to see differently and are there topics on which you would like to receive more information? We greatly appreciate any feedback, so please let us know!

Botrytis control

Because of its fast growth, the peony is hardly resistant to climate change. One of the resulting damages is almost certainly Botrytis. The fungus will especially keep causing problems when the peony doesn’t get protection during growth. In that critical period extra sprayings of the peonies are absolutely necessary. Good and effective resources in that case are Teldor, Kenbyo, Luna Sensation and Switch. The best result is obtained when the buds are wet with dew. The fungicide then flows around it more easily. You can also use a good spreader. And spray from both sides.

When Luna Sensation is being used just before the flowers start to bloom, it means that there will be a very low percentage of Botrytis in the flower buds. But it also ensures a remarkably low failure in the holding cell.

In terms of a weak crop, don’t spray for two days after night frost.

The so-called flower bud-Botrytis is the same Botrytis that causes collapses in your crop. Therefore it goes without saying that plots which have had many collapses are most prone to flower bud-Botrytis. It is very important that enough calcium and silicon (provides stronger leaves / cells for better protection against fungi) is available.

A major problem every year is bud loss with peonies. Although Botrytis grows most quickly during wet and warm weather, the biggest problems arise during cold and wet conditions. Just before flowering. In that case the flowers do not ripe off and will be on the plant too long in a fragile state.

And the fungus will grow into the flower bud from the little leaf underneath the flower. If the weather conditions become warm and humid, the flower buds will collapse in large numbers.

Phytophthora

A quite new infestation in peonies is known as Phytophthora. An infection which takes place through injuries under humid circumstances. The fungus can survive in plant tissue and in the soil for years. The first infestation can be recognized through black and weak leaves in the crop. When there is an infection by Phytophthora in the spring, brown to gray black spots will arise on the stem parts. In that case the branches will come up like some sort of black brackets and they will not grow further than ten centimeters. After infection it is almost impossible to remove. Places of infection will most of the time feel spongy and soft, where the marrow will be dark brown and wet rot. Kansas and Duchesse are examples of species who are sensitive to Phytophthora.

The elements Manganese and Zinc offer resistance against Phytophthora.

To prevent this, from the moment the flower rises till the mulching, you have to spray with, for example, copper, Moancozeb, Axidor (works systematically), or the new fungicide Ranman Top.

Click here for all the information regarding Phytophthora.

Nematodes

The so-called ‘predator’ nematodes are predatory nematodes. These are the direct natural enemies of the harmful species. Saprophages are nematodes which do not damage the plant, but they do break down dead organic material, for example. The higher the numbers of these saprophages, the better the soil life of a plot. On top of that, it is more likely that the good and harmful soil life will balance each other.

Leaf nematodes:

An infestation of nematodes is clearly visible because of the deformity of the leaf. In that case the tissue looks misformed and the leaves are half grown. The growing point can sometimes dry out by young shoots.

It is also possible that bud dehydration (bud abortion) occurs. Clearly identified by black, rotten flower parts with healthy petals around. The flower buds can dry out in every stage. Sometimes the flower bud will come into bloom, but the flower is misformed.

Click here for all the information regarding Nematodes.

Common swift (moth)

Root borers are ground-dwelling larvae of butterflies. These caterpillars are very harmful to various horticultural crops, because they eat at the roots of plants underground.

The caterpillars hatch between May and mid-July. And in the greenhouses often before that period. They are about 6 to 7 mm long when the eggs hatch and they can grow up to a length of 4 cm. They are transparent to white in color and the gut contents can sometimes be seen as a black streak through the insect. Caterpillars of the common swift (moth) have a brown head and large jaws. They are very mobile; if you put them on the floor or on your hand, they squirm to get away. Depending on the temperature, the caterpillars pupate between March (greenhouse) and mid-June.

Click here for all the information regarding Common swift (moth).

KaRo

Peonies grow from nothing to a full grown plant in a very short time. Which cost a lot of energy. The plant needs a range of main and spore elements to make this possible. These elements are not always as readily available through the soil. Because of the low soil temperature and/or high pH value of the soil. Therefor it absolutely makes sense to provide the crop with these elements through leaf nutrition.

Click here for all information from KaRo.

Leaf roller

Leaf rollers owe their name to the fact that the caterpillars string themselves between the leaves. And that causes the leaves to roll up. In the case of peonies, this little black caterpillar eats its way to the flower bud of the plant. This roller isn’t only hard to find, but the creature also causes damage directly to the flower bud. Therefore controlling regularly on leaf rollers is necessary.

Mole crickets

Mole crickets are digging insects with highly developed forelimbs. They can get about 5 centimeters big. They live of larvae (cutworms and leatherjackets) and other soil insects. Supplemented with plant material.

The color of mole crickets varies from brown / red-brown to yellowish. To create corridors just beneath the soil surface, these mole crickets use their forelimbs as excavator. These corridors are used more than once. When digging, they bite off roots of a variety of crops. With all its consequences. These creatures are good at flying. Often on warm evenings. They occur in wet meadows, peat soil, plots and gardens bordering ditches.

Click here for all the information regarding Mole crickets.

When planting peonies in fall 2021; benefits of investing in 3-5 eyes compared to 2-3 eyes:

Number of stems/flowers per plant (2-3 or 3-5 eyes):

Variety Year Amount of stems Amount of stems
    2-3 eyes 3-5 eyes
Sarah Bernhardt Planting in fall: 2021    
  Spring              2022 0 0
  Spring              2023 0 3
  Spring              2024 4 7
  Spring              2025 6 8
  Spring              2026 7 9
  Spring              2027 7 9
  Spring              2028 8 9
    32 45

Have a look at our product pages for more information regarding our cut flowerspot plants and peonies.

For more information about our products, please contact: