Gardening - February, 2015By Rhea Hamilton-Seeger
Acid-loving azalea gets tented for winter with hopes the mice will stay away
Part of the joy of gardening for me is solving some of the challenges I face. These challenges usually involve impulse buys and a learning curve.
When we bought the farm so many years ago, I thought a blueberry bed would be a fabulous idea. Klaus and I set up a bed with old beams and filled it with peat moss mixed with the soil. I thought it should have worked but we were both busy and the weeds took over and more importantly the plants never really prospered. There was a severe lack of water and the plants were just not happy here.
The blueberries did not thrive but I have not given up the idea of planting acid-loving shrubs here.
I wrote to you about my azalea last November and have uncovered some more insightful information. Years ago I bought my first azalea which is in the same group of acid- loving plants but this time I planted it in the garden that I see every time I go out my door. It offers dainty clusters of wee lavender blooms early in the spring. It is so pale that at first glance you almost miss them but a few days later as more blooms appear it becomes quite festive looking. Water is still an issue. While the leaves are leathery and will withstand some droughty conditions, here on the gravel ridge they do need a drink when the when rain is slow to come.
Azaleas were developed from various species of rhododendron. The University of Minnesota developed and introduced the Northern Lights series in 1978. These azaleas prefer sun to partial shade and a rich, moist, acidic soil. They are long lived and in my garden that means they are just a bit more tenacious than other plants. Since that initial release there has been a burst of new varieties. The colours go from pastel to vivid shades of orange (my favourite), to red, white and pink, lasting anywhere from two to four weeks. Those in sunnier locations will not last as long as those in shadier spots.
I see them in the garden centres every spring and I am curious as to where people plant them. They can grow anywhere from 30 inches or 75 cm high and wide as 40 inches and seven feet tall. That must be in perfect conditions!
They can be featured in rock gardens and used in the understory of evergreens where there is increased acidity in the soil. As I write this I look out at the large evergreens in our east garden and realize my next azalea will be right there nestled on the north east side of the 30 foot spruce and equally tall weeping cypress.
Once you have selected a site it is important to prepare the soil around your new plant. Dig the hole twice as large as you need and fill it with half topsoil and half peat moss. Water well after planting and mulch with bark chip, oak leaves or pine needles. Like so many plants, a bit of fertilizer in the spring would be appropriate. There are brands of plant food geared for acid loving plants. I used to think aluminum sulphate was the best choice but have learned that ordinary sulphur or ammonium sulphate is the one to look for. A small amount of sulphur added to the soil each year will keep the soil acidic. I did a bit of checking on the differences. Ammonium sulphate slowly releases an ammonium ion in damp soil. This creates a small amount of acid, which lowers the ph of the soil. A cheap, artificial fertilizer, it also contributes nitrogen to the soil. But be careful not to get any on the leaves of your plants. Ammonium sulfate is also an effective herbicide when applied to leaves where it will burn and leave a plant weakened or dead.
You can prune for shape and deadhead the spent blooms, being careful not to nip next year’s buds. Think of lilacs, which set their next year’s blooms this year.
Winter is always a challenge. While azaleas are bred to withstand temperatures from -34 to -45 C. they still need some shelter from drying winds. Some varieties drop their leaves in the fall and others hold onto them.
My one pale lavender azalea on the west side of the house is sheltered by boxwood and trees and I have never covered it. The two new ones on the north side are more in the open.
This year I drove three stakes around the plants, wound burlap around the stakes and created a flap over the top. I stapled the burlap to the stakes and then wrapped binder twine around the whole bundle. It is recommended to fill the ‘tents’ with leaves and since this attracts rodents, place some mouse bait around the base. I am not a big fan of mice but I am the first one to stomp around the garden cursing the damage done by the critters.
My supply of leaves was too wet and I am hoping that the burlap will suffice this year. The tents, as of January, are still mostly intact. I think I will have to use wider stakes next year to offer more surface to staple to. I am excited to see what blooms this year as my new one is Mandarin Lights and features large trusses of deep orange flowers.
One last note: I had a lovely call from a gentleman eager to find a variety of native maple tree that features the reddest colour. We had a conversation about what causes the great change of colour in maples and he believes that while we understand it is created by environment, there may be a bit of genetics at work here. So if you have a picture of a green-leafed maple that consistently shows red in the fall, I want to hear from you! ◊
Rhea Hamilton-Seeger and her husband live near Auburn. She is a skilled cook and gardener.