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Best Soil For Growing Peonies

Publish Data: March 12, 2021

by Abid Hasan Khan

Do you want to choose the best soil for planting peonies? While planting peonies both indoors and outdoor, you may face many problems related to soil. If proper action is not taken quickly, your bloom may delay and disease might attack the plants. In this article, we will discuss the best soil types, conditions and how that soil can be prepared to avoid bad outcomes.

Peonies prefer loamy and well-drained soil that has an average pH of 6 to 7. If your soil doesn’t have enough organic matter, slow application of fertilizer will help to become nutritious. To know more about the best soil conditions and fertilizers required to grow peony flowers, follow along with us to the end.

Planting peony in soil
Chantal GIRAUDEAU / Flicker

Ideal Soil Conditions for Outdoor Peonies:

  • Plant peonies in soil that gets adequate sunlight for a minimum time of 6 hours. Avoid planting under the shade of trees that are bigger than peony. Otherwise, your peony plants may become malnourished due to competition for soil nutrients, water and air.
  • Loamy soils that are already broken into small pieces are ideal for herbaceous and Itoh (intersectional) species; they don’t grow well in hard soils that are tough to penetrate. If your soil is not well-drained it will become soggy and form large clumps of clay near the roots. In this case, try to mix one or two cups of sand into that soil to increase its draining capacity.
  • Most of the herbaceous varieties prefer neutral or slightly alkaline soils. The tree peonies require a sheltered position. Compared to the herbaceous and intersectional varieties, tree peonies are more tolerant to acidic soils than the
  • Avoid lower grounds and waterlogged areas. Peony plants grow well in a comparatively high or slope area where rainwater doesn’t stand for long.

Best Soil Condition for Indoor Peonies:

  • Fill the container with a well-drained potting soil. Try not to use standard potting soils that does not provide enough drainage as peony roots are vulnerable to rot.
  • Use containers that can hold up to 24 inches of soil. As herbaceous peonies have large root systems, they may not grow properly in soil if your container is not big enough.
  • Water the potted peony once a week and make sure that no excess water stands near the plant stem. Otherwise, the root may rot and yield no flowers.

Ideal pH of Soil and How to Achieve it

Try to keep the pH of your soil from neutral to slightly acidic, that is from 6 to 7 on a pH scale. If you can perfect the soil pH in the fall, you will receive better results in the upcoming spring season. There are some tricks to determine if your soil has a correct pH or not.

  • Get a proper soil analysis from your nearby testing laboratory.
  • Purchase a soil test kit from a nearby garden center.
  • Take help from your local soil specialist, if available.

After the test results if you find your soil too acidic, you can raise the pH by adding ground limestone when it is moist to higher pH above 7. On the other hand, if your soil is very alkaline, add Sulphur or Aluminium Sulphate to increase the acidity and lower pH below 6. Avoid adding these chemicals excessively into the soil. Otherwise, you will get a negative outcome. Always take help from your local garden centre or garden specialist. They will recommend which chemicals to apply at what rate based on your soil type and pH.

What fertilizers are best for Peonies?

Among many fertilizers, you will find 5-10-10 low nitrogen fertilizer the ideal one for growing peonies. It has 10% phosphorus, 10% potassium and 5% nitrogen. Osmocote’s fertilizer and Earth 707P fertilizer contains essential nutrients for your soil. It will enhance the color and growth of your flowers in both winter and spring. You can use them for both indoor and outdoor space.

How to Prepare Soil for Peonies?

  • Spade the soil to a depth of 12 inches to 15 inches before planting the peony bulbs.
  • If you have clay soils, drainage of water can be a problem for the stem and roots. In this case, mix crushed stone, compost or rock dust into the soil to make it a more sandy.
  • If you have sandy soils, provide compost mixed with water to increase the amount of nutrients in the soil. This will further help to retain moisture and help the plant to store water and food.
  • If your soil doesn’t have enough nutrients, use fertilizer when their initial growth is about 2 or 3 inches above soil level. Apply 5-10-10 low nitrogen fertilizer into the soil around the base of the plant. Don’t use an excessive amount of fertilizer, apply only one or two cups per plant and apply near the stem.
  • Be careful not to disturb the peony roots while adding fertilizers. Don’t apply fertilizers too close to the roots. This may even start root rot. Try to avoid the eyes (initial flower buds) while applying fertilizers.
  • If you want your soil to conserve more moisture during spring, add 2 or 3 inch layers of organic mulch. This will gradually add organic material into your soil and increase its new nutrient value.
  • In case of potted peony, ensure that the soil has a mix of 35% perlite and 65% topsoil.

Although peonies are very resilient and can use natural organic material to get nutrients, proper soil is necessary to achieve better blooms. Rather than planning to apply fertilizer, try to prepare the soil properly at the initial stage before plantation. As a result, you will require less amount of fertilizers to apply. Your hard work will surely get paid off some day and your garden will bloom with beautiful peony flowers.