|I have a golden smokebush which I planted in early July of this year. Recently, a lot of the newer leaves are turning dark brown on the margins of the leaf up to almost the middle of some leaves.
The plant is growing great and otherwise appears healthy except for this browning of the leaves.
|Foliage symptoms such as you described can actually indicate both over and underwatering. Midsummer is the most difficult time of year to transplant because the new plant is subjected to seasonal heat and drought stress before it has had a chance to become rooted and begin to establish itself in the new location. I suspect it is suffering from dry soil; although quite drought tolerant once it is established and fully rooted, this plant still needs to be watered regularly for the first year or two. The soil should be kept evenly moist like a wrung out sponge, not saturated/sopping wet and not dried out. To know if you need to water, dig into the soil with your finger. Check both the potting mix and the surrounding soil as they can dry at different speeds. IF it is still damp, do not water yet. When you water, water slowly and thoroughly so it soaks down to the deepest roots. Check on water needs until the soil freezes this fall. Using an organic mulch several inches thick can also help keep the soil more evenly moist; layer it two to three inches deep in a flat layer over the root area.
Overfertilizing and chemical exposure (such as herbicide or insect spray) can also cause foliage burn. This plant needs only average fertility to thrive, so an annual application of compost and/or general purpose fertilizer (either slow release or granular form) should be adequate. Apply this in the spring, using a product with an analysis of 10-10-10 or similar per the label directions. I hope this helps you trouble shoot.