Seldom growing taller than 12 feet, the mountain laurel attains a manageable size that makes it perfect for a spot where a smaller tree may be appropriate. Kalmia latifolia is hardy in USDA zones 4 through 9 and prefers a location shaded by taller trees, especially in regions where afternoon sun becomes really hot. Mountain laurels are best left to grow naturally, so little if any pruning is necessary or desirable for these remarkably undemanding plants.
Plant your mountain laurel in a well-draining shady to partially sunny location after all danger of frost has passed for your area. Position the laurel so the crown is just above the soil surface. Acidic soil is preferred, with a range of about 4.0 to 6.5 being ideal. Amend the planting area with peat moss if you need to increase acidity.
Apply 2 or 3 inches of an organic mulch such as pine needles, leaves or wood chips. This will help to conserve moisture and discourage weed growth.
Water the mountain laurel thoroughly, to a depth of about 10 to 12 inches. These plants love evenly moist soil, but won’t tolerate wet feet. Soak the mountain laurel once about every week or 10 days throughout the growing season, and once more just before the ground freezes during the plant’s first year. Once established, you’ll only need to water during extremely dry spells, and once right before the onset of freezing weather each year.
Feed the mountain laurel with an all-purpose fertilizer for acid-loving plants once each spring or fall.
Deadhead flowers as they fade from April through June. This will encourage seasonal blooming and increase next year‘s flower production.
Prune out dead, damaged or diseased limbs as they occur throughout the growing season. Other than that, mountain laurel needs no pruning and looks best when allowed to maintain its natural growth habit. Trim up stray stems here or there if you desire a tidier appearance.
Protect your mountain laurel from severe winter weather in zones 4 and 5. Cover the plant loosely with burlap and add several more inches of mulch to the roots.