Once the snow is melted, the peonies are beginning to wake up. We generally leave a few inches of natural mulch, i.e. leaf litter around our peonies for the winter. With our herbaceous and intersectional peonies (as shown above) we leave 2-3"of stem in the fall so its easy to find them in the spring even when they are covered with mulch and the eyes are just beginning to peak through.
We feel its best practice to remove any mulch from the base of the peony. With herbaceous and intersectional peonies (as shown above), removing the mulch ensures that new growth will not be inhibited. With tree peonies, its also a good idea to remove the mulch from around the stems, as this can trap excessive moisture moisture and lead to fungal issues.
A blend fertilizers and soil amendments for successful peony growing.
At Cricket Hill Garden we use these three soil amendments in combination around all of our peonies in the spring. We use the lime to raise the pH of the soil. Our natural pH is around 5.5, but with regular application of lime we have succeeded in raising it to around 6.5, the minimum threshold for good peony growth. We like to use calcitic lime because it contains a much higher percentage of calcium than regular garden lime. Calcium is a vital mineral to have in the soil; it helps the plants to form strong cell walls which are naturally more resistant to stress and disease. Calcitic lime also contains very little magnesium. Too much magnesium in the soil can render certain nutrients present in the soil unavailable to plants. NOTE: If you have applied lime in the last year, it is not necessary to do so again now. Just as peonies resent a low pH soil, they will also struggle in soils with excessively high pH. If you are unsure of your soil's pH its best to have a soil test done to understand your baseline. Most state universities or state agricultural experiment stations preform this test for a nominal fee. See for example, the UCONN Soil Lab.
Azomite, a crushed volcanic rock powder, contains 70 different minerals and trace elements. These micro-nutrients help facilitate healthy plant growth. We have found to be an excellent supplement for our peonies, other perennials as well as in the vegetable garden.
Finally, we add a handful of low nitrogen fertilizer to the drip line of the peonies. We like to use North Country Organics Pro-Gro (5-3-4). It is blend of Natural Sulfate of Potash, Phosphate Rock, Vegetable Protein Meals, Animal Protein Meals, and Natural Nitrate of Soda. Again, this fertilizer is also very good for giving seedling transplants in the vegetable garden and young fruit trees an extra boost of energy. Another good organic fertilizer to use would be Espona Bulb-tone (3-5-3).