Minnetonka Rhododendron

Nothing can match the beauty of rhododendrons when they are blooming, with their large, showy blossoms in dynamic, brilliant colors. In bloom a bush is smothered so densely in flower clusters that the foliage is almost completely hidden. Even out of bloom their attractive evergreen leaves have a calm beauty of their own, which gives the garden a fullness and completeness. If you have suitable acidic soil, you should certainly be growing these beautiful plants to enhance your spring garden, perhaps with re-blooming azaleas in front to continue the display into the fall. The perfect rhododendron will be dome-shaped, with attractive foliage and a bold display of large flowers, and that’s exactly what you get with the Minnetonka Rhododendron. Its rich purple blooms glow vibrantly across the garden, and this is also a very hardy selection, which grows perfectly even in zone 4.

Growing the Minnetonka Rhododendron

Size and Appearance

The Minnetonka Rhododendron is a dome-shaped evergreen shrub, growing to about 3 feet tall and 4 feet wide within 10 years. Older plants can reach as much as 6 feet tall, in time. The growth is neat and dense, with flowers produced over the whole plant. The oval leaves are glossy, dark-green, and smooth, about 3 inches long and 1 inch wide, with wavy edges adding to their charm.

Flowering takes place in May, and every branch ends in a large bud, containing about 15 blooms in a dense cluster. Each bloom is funnel shaped, with wavy edges, and 2 inches wide. The buds are a deep reddish purple, opening to a bright pure purple both inside and outside the flower. The beauty of each bloom is enhanced by the ruffled edges and by the cluster of vivid yellow-green spots in the upper part of every bloom – it is truly a gorgeous sight when in bloom.

Using the Minnetonka Rhododendron in Your Garden

This plant is perfect for the front and middle of beds around your garden. Set aside a special area for azaleas and rhododendrons, or mix them into your beds, as you choose. Grow it in woodland areas, or in more structured parts of the garden where its neat dome-shaped form will fit in perfectly. Grow it in pots and tubs as well. With their fine root systems, you can grow rhododendrons for years that way, and its ideal if you don’t have suitable soil. Plants in pots will need to be in zone 6 if they spend the winter outdoors. In zone 5 and 6 simply bury the pot to its rim in a garden bed.

Hardiness

Bred in Minnesota, the Minnetonka Rhododendron is a great choice for zone 4, where it is hardy in all but the very coldest parts of that zone. Evergreen rhododendrons that will take so much cold are rare, so take advantage of this one, which you will love. It will of course also grow in warmer zones, all the way to zone 8.

Sun Exposure and Soil Conditions

Morning sun and afternoon shade are ideal for this plant, or light dappled shade from tall deciduous trees overhead. The north side of larger plants, or walls, is also perfect, with clear sky overhead, but a shadow to protect from sun-burn. The soil should be moist but well-drained – this plant is not drought tolerant, but it doesn’t like wet, soggy soil either. The soil should be acidic, with a pH reading of less than 6.5. If you don’t have suitable soil the simple solution is to grow it in a pot, using potting soil blended for acid-loving plants. Feed potted plants regularly with a liquid fertilizer blended for azaleas or rhododendrons.

Maintenance and Pruning

Once the soil conditions are right, there is little to do but watch the Minnetonka Rhododendron grow. It needs no trimming or special treatment, just a mulch in spring with lime-free organic material, and attention to watering during dry periods. Pests and diseases are rarely problems. You can pinch off the spend flower heads after flowering, to prevent seed forming, which will maximize blooming the following year. Plants in zone 4 should be watered deeply in late fall, and the use of anti-desiccant spray for winter protection would be helpful in zones 4 and 5.

History and Origin of the Minnetonka Rhododendron

Rhododendrons mostly come from China and the Himalaya Mountains, although there are species growing almost everywhere in the world. There are many different selected garden forms and the variety called ‘Minnetonka’ is the work of a Minnesota nurseryman, Henry Motzkau. He had a nursery in Whitewater, Minnesota, and he created many new azaleas and rhododendrons. This one was a lucky seedling, probably from Rhododendron ponticum crossed with an unknown second plant. That tough and reliable species grows naturally all the way from Spain across to Turkey and Georgia. It has produced many valuable varieties. Henry Motzkau found this plant around 1965, but it was only after he died that it was officially registered in 1990 as a new variety, by Van Veen Nursery, in Portland, Oregon.

Buying the Minnetonka Rhododendron at The Tree Center

If you are new to rhododendrons, then this tough and reliable plant is a great place to start. If you are not, it will certainly be a superb addition to your collection. Either way, order as soon as possible, because we only have a limited supply, and this plant is always a popular and fast selling variety, especially for gardeners in the north.