|I have a Cornus pumila planted in the north side of our house where only recieves partial sun (about 4-6 hours depending on the season). It has been there for at least 4 years, and besides the powderly mildew that I have been succesfully preventing ever since the first year with a sulfur base fungicide, the tree looks very healthy and has grown probably about a foot tall and wide since it was planted, but it is not blooming. Is this a common thing with young dogwoods, or perhaps it needs more sun light? Is there somethin that I can do to help the tree bloom next spring?|
|Cornus pumila is a dwarf shrub, very slow growing to a mature size of only two to three feet tall and as wide or a bit wider. It does tend to be slow to bloom so immaturity is probably part of the reason. Overfertilizing can also cause it to grow vegetatively at the expense of blooming but it doesn't sound like that would apply in this instance -- as long as the foliage is not oversized.
However, it is usually recommended for a location with full to partial shade. Full sun is a minimum of six hours of direct sun including the hour of noon. From your description of the lighting I think it might do better with more sun (depending what time of day it is receiving sun now.) This dogwood is also considered quite resistant to mildew and other foliage problems, so in a more open location with better air circulation that might not be a problem. On the other hand, it needs a cool location with evenly moist yet well drained soil, so the north side could be the better choice since your summers are so hot.
You could consider moving it to a location with full direct sun all morning longat most or very bright dappled light all day at minimum (and good air circulation and where the soil would be evenly moist yet well drained) and see if that helps, moving it early next spring. I'm sorry I can't give you a more specific answer on this, it is more a judgement call you need to make based on how the plant looks and performs than a clear cut answer. But, I hope this helps.