Question: I have a youngish acer that I bought last year from a good quality garden centre. It has never looked too happy, even after I just bought it. The foliage dries up and shrivels even out of the hot weather we've been enjoying. It's in a large pot and watered regularly. It's in full sun which I didn't think was an issue, but am guessing it needs some shade. I appreciate there are many types of acer, but any suggestions are welcome.
Answer: Acers are susceptible to leaf scorch, especially in windy and, or hot conditions and the more filigreed the leaf, the worse the scorch can appear. The purple leaved cultivars need more sunshine to develop good colour tones, but certainly the green forms can do well in a partially shaded spot.
You say that the plant is well watered, so it should be able to grow in a position in full sun. There may be a problem with the roots not being able to take up the water. Ensure that the acer is potted up gradually into larger containers.
The pot should only be a couple of inches wider and deeper than the rootball each time. In large volumes of wet compost, the finer roots can rot, limiting water uptake. Among the best acer performers are A ‘Bloodgood’AGM, A. ‘Osakasuki’ AGM and A.‘Sango Kaku’ AGM.
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