I have a 3 to 4 foot tall rosemary plant hedge I have growing in my median strip between the sidewalk and the street curb. They have grown quite well and bloom several times a year. I have always watered them in the hot dry summer but I wonder if it is necessary or do they like a dry environment. They do seem to grow quickly for rosemary variety. I am not sure of the species but they were in the bargain shelf at our local big box store. I notice that now as they have become larger they tend to keep other weeds and grass from around their base.