Rhododendrons can be planted here, but it will take some work
Will rhododendrons grow in the Grand Valley?
Rhododendrons will grow here, but not without some preparation and ongoing maintenance.
Some rhododendrons aren’t winter hardy for us, but there’s a group called the H-1 hybrids that have plenty of cold hardiness.
However, it’s not the winters that usually give them problems here, it’s the summers. Rhodies like a cool, humid climate (think Seattle) and rich, organic, well-drained, acidic soil. Basically, we don’t have any of that here.
To grow a rhododendron here you need to try to create a spot in your garden that’s as close to Seattle as you can, and I’m not talking about planting them on the west side of the yard.
The first thing to do is to plant it in the shade. They like pretty bright light but need to be protected from that scorching afternoon sun. I’ve found that it’s also helpful to plant other plants around them and use an organic mulch on the ground such as bark chips or cedar mulch. This helps to raise the humidity in that area.
You also want to do a great, and I mean really great, job preparing the soil before you plant. You want to amend the soil well out from the plant with lots of well-decomposed, low-salt organic matter such as Soil Pep, peat moss or compost. I’d mix it half and half with the soil from your yard.
Amend the soil to a depth of at least 12 inches (18 inches is better) and as far out around the plant as you’re able. And lastly, regularly feed the plant with an acid forming fertilizer such as Mir-Acid.
I know this is a bit of a hassle, but they’re so beautiful in the spring!
When we lived in Parker, our neighbor had a mugo pine bush in their front yard. Would that grow here? Can it tolerate a lot of sun? Hers was shaded in morning but got afternoon sun. Please let me know if you think it will grow here.
Though the size and shape can vary from variety to variety, these are usually smaller (three to five feet tall) shrub pines with dark green needles and a rounded to slightly spreading growth habit.
A number of years ago we decided to only sell named varieties of mugo pine. The old ones we used to sell (and you still see commonly in the trade) are called Dwarf Mugo Pine or a Pumilio Mugo Pine.
The problem with this plant is that it is grown from seed and though it is smaller than the species (which can get to 15 or 20 feet), it is variable in size and usually gets bigger than what most people expect. I field lots of calls from folks who want to trim back their eight-foot-tall “Dwarf Mugo” because it has gotten much bigger than they expected.
Though it can be done, the timing of the pruning is important, and it’s just one more thing to do out in the yard. I don’t know about you, but I’m not looking to add chores out in the garden.
These named varieties are reliable and predictable in size and growth habit. The two varieties of dwarf mugo we carry are Slowmound and Teeny.
Slowmound grows to three to five feet tall with an equal or slightly greater spread. It has very dark green needles that form a dense, compact mound.
Teeny is even smaller, growing 18–36 inches tall with a slightly greater spread. It has smaller, finer needles than Slowmound that are a rich dark green, gaining a very slight yellowish cast in the winter.
One thing to keep in mind about these truly dwarf mugos is that they’re pretty slow growing, so prepare to be patient. And though they cost just a bit more than the seed grown plants, I think it’s worth the cost to know what you’re getting.