By adding bark mulch, you can protect your perennial bed from weeds and also ensure that moisture remains (better) in the soil. But be careful: not all perennial species tolerate this form of mulching. Our article explains everything you need to know about bark mulch for perennials.
Which perennials tolerate bark mulch?
Not all perennials tolerate bark mulch. Rockery, prairie and steppe perennials should not be mulched with bark mulch; instead they can be covered with grit or volcanic ash. Forest or forest edge perennials tolerate a 3-5 cm thick layer of bark mulch - however, nitrogen fertilization and good water drainage are important.
General preliminary remarks on bark mulch
Basically there are two types of mulch:
- organic mulching material (bark mulch, cocoa shells)
- mineral mulching material (gravel, slate)
General benefits of mulch
- reduces weeds
- retains moisture in the soil
- compensates temperature fluctuations
- protects plants from freezing in winter
- ensures cleanliness in the garden
- avoids siltation
- stops dogs from doing their “business”
What exactly is bark mulch?
Bark mulch is a waste product from forestry and also from the wood processing industry in sawmills. This mulch is cheap and is therefore very popular with hobby gardeners.
How to properly use bark mulch on perennials
Rock garden, prairie and steppe perennials generally do not tolerate bark mulch or similar material. Logical, after all, these species are not forest or forest edge plants, they are not familiar with the mulching materials in their natural habitat.
Recommendation: However, you don't have to completely forego mulching these types of perennials. You can sprinkle the gaps with grit, volcanic ash or similar materials.
Bark mulch for forest or forest edge plants
Perennials that belong to the forest or forest edge plants naturally tolerate a three to five centimeter thick layer of mulch made of bark mulch or other organic mulching materials.
Attention: On heavy soils, good water drainage must be ensured under the mulch cover. If this is not possible, you should avoid mulching. Otherwise, the perennials cannot develop well during the growing season and become susceptible to fungal diseases.
If you use bark mulch on perennials on permeable soil, you must not forget to fertilize with nitrogen, otherwise a deficiency can occur. This is because fresh bark mulch often contains herbicidal tannins that remove vital nitrogen from the soil.
Our advice: If possible, use seasoned mulch (€13.00 on Amazon) (less herbicidal tannins) and (still) fertilize with nitrogen. Then there is usually no problem.
Note: Before you cover your perennials with bark mulch, you should prepare the soil well. The entire area must be free of weeds.
Tip
The denser your perennial bed is planted, the more likely you are to avoid adding bark mulch. However, be sure to adhere to the minimum planting distances.
