Answer: You are welcome!
Dahlias will bloom better if you do remove the faded flowers. Cut just above a leaf, or just above a stem joint to avoid leaving a bare stem stub sticking out.
Rhododendrons suffered this past winter due to the oscillating temperatures and then the unusual spring. The best you can do for them is to top dress with compost, and perhaps use a slow release granular fertilizer such as Hollytone. Read and follow the label directions for how much to use.
Then keep them mulched. Use about two to three inches of organic mulch such as pine bark. Spread it out over the root area in a flat layer and do not allow it to touch the stems.
You could also water if needed to supplement rain so that the soil stays evenly moist, meaning damp like a wrung out sponge, not sopping wet/saturated and not dried out.
I hope this helps!
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