- Easy to plant under: deep and heart roots
- Difficult shallow roots
- Underplanting trees - How it works
A garden is especially lush green and homely when it is planted on several levels. Especially if there are many larger trees on the property, their often bare tree discs are not very impressive. With a few tricks, however, even this difficult region can be brought to life with plants.
Deep-rooted trees can easily be underplanted
Easy to plant under: deep and heart roots
Trees such as oak, pine, apple and rowan are easy to plant under because they only develop a few main roots, most of which grow deep. Thus, your tree pit is mostly free of roots, which compete for water and nutrients with perennials and flowers underplanted. You should therefore have no problems planting suitable perennials, ornamental grasses, summer flowers, ferns or even low shrubs with deep and heart roots. However, there is one restriction: the species selected for underplanting must be shade-tolerant, and the existing soil conditions (moist / dry, nutrient-poor / nutrient-rich) should also be taken into account.
Difficult shallow roots
On the other hand, the underplanting of flat-rooted plants such as maple, spruce or birch is much more difficult, as their roots grow densely through the tree disc and thus dig up the water for other plants. Other species such as beech and horse chestnut grow very densely, so that hardly any light falls on the tree pit. Here, underplanting is difficult, if not impossible, due to the unfavorable light conditions. Other trees, such as the walnut, have developed a different strategy to get rid of unwelcome competitors: their autumn leaves contain essential oils that prevent other plants from growing.
Underplanting trees - How it works
With a few tricks, however, you can plant at least a few onion plants under some flat-rooted plants. Spring bloomers such as snowdrops, snowflakes, crocuses or tulips are rarely swayed by the strong root pressure, and their bulbs fit comfortably between the roots. If the soil is heavily rooted, a thick layer of topsoil applied to the tree disc will help. However, leave at least 20 centimeters of space around the trunk so that the tree is not constricted. You should always clear away the autumn leaves of many trees such as walnut and co. for a successful underplanting, otherwise the plants will soon die. After underplanting, mulch the entire tree disc thickly with bark mulch to retain valuable moisture in the soil.
tips
The best time for underplanting is late summer from the end of July, as most trees have completed their growth by this time and the need for water and nutrients is no longer as great.