Mint Shrub. Where has this little sub-shrub been all of my life?! A relative of Buddleia, it can be treated similarly by pruning it back heavily in late winter. Normally it puts on a display of its fuzzy pink spires in the fall, but here in the Deep South its starts to grow so early, that we are usually treated with a flush of flowers in late March through April. If this happens, I would recommend pruning back the spent flower heads to induce a good flush of new growth for the fall when it normally flowers for the rest of mankind. Grow on just average, well drained garden soil.