I’m looking for some advice from any of you who’ve grown roses in a desert climate. Specifically in or around the Coachella Valley in California though any hot desert climate will do! (Warren, I think you regularly get some HEAT down under, no?)
There are a lot of roses that are forced to grow out there but none of them are particularly beautiful or elegant looking. A lot of stiff looking plants with burnt up flowers. The temps average up to 120F in the summer and down to just above freezing in winter. Winter highs can be in the 70 degree range so there’s no real chance of a dormancy period other than a forced one.
Also – perhaps more specifically for Jim – has anyone tested any of the new hulthemia hybrids in desert climates? I’m wondering if their original genes/roots make them more tolerant of the heat.
While I am not in the desert we do suffer through so really hot dry summers. I can tell you I have two roses that tend to do better in the heat. Caldwell Pink will not even bloom until the temperatures rise in June and July. Perle 'd Jardin tends to ball in the damp spring but blooms nicely in hot dry weather, it is the reason I keep this rose because it will do well in the summer. I will say that both of these roses do get a bit of shade in my garden.
For several yrs I lived in first Mesa and then in Tucson Arizona which has close to comparable temps as what you are experiencing. Mesa, AZ has an active rose growing Mesa, Az rose club and you can find lots of suggestions here at their site. One thing about growing roses in the desert is that they are best allowed, even encouraged to go semi dormant in the height of summer and then have a little pampering in the fall when nites start to cool and you will get a nice long fall bloom. Roses with heavy petal substance ,i.e., Marilyn Monroe, Moonstone, and St. Patrick types do well there.