Boxwood can also be damaged in winter and due to long periods of frost. This then manifests itself in yellow or brown leaves. There are three causes for this symptom in boxwood: the dreaded shoot death, a lack of nutrients or drying out during the frost period.
Often, the lack of water in the Buxus only becomes noticeable when the dry period is long over. The result is the described leaf damage, especially in spring after prolonged frosts. This late damage is then often very protracted and can even sometimes result in the death of the plants. Possibly also the roots of the plant are attacked by the very long winter.
What you can do
You should now provide your boxwood with a slow-release fertilizer. Mature garden compost enriched with horn shavings is suitable for this purpose. Of course, you can also buy special boxwood fertilizer, e.g. Azet BuxusDünger from Neudorff. Mulching with compost, bark mulch and the like is advantageous, as this preserves soil moisture. However, it takes some time with the new shoots until the fertilization or soil improvement is clearly noticeable.
This also applies to box trees in containers. Here you can also check the condition of the roots. To do this, take the tall stems out of the containers and at the same time give them new, enriched soil (see above). Box trees are not so sensitive and usually recover even after these winter hardships.
By the way, boxwood tolerates pruning into the old wood very well, it develops new shoots and becomes more compact. Severe pruning is also possible if boxwood is becoming bare from the inside or suffering from late damage (see above). Boxwood should not be pruned after mid-August, otherwise the plants are stimulated to late new shoots that can no longer fully mature. The result will then be frost damage again in winter.
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