Anti-transpirants and Anti-dessicants for Rhododendrons
Anti-dessicants and Rhododendrons
A number of years ago I came across a bottle of Anti-transpirant and I wondered how the material was used. So I’ll attempt to answer my readers, question about this material here. My reader asked me about anti-transpirants or anti-desiccants both are compounds that are applied to the leaves of plants to reduce transpiration for the most part. They consist of a colorless film on the leaf surface which allows diffusion of gasses but not of water vapor. Examples of the anti-transpirant include silicone oil and waxes or anti-desicants including pine oil. This compound, Anti-transpirant, is also the material you might see being sprayed on Christmas trees when they are being harvested out in the fields, or on plants that are being harvested such as flowers that are going to a florist.
Each year during the winter when the temperatures are cold for an extended period of time and the soil freezes below the roots, you will see the evergreen leaves on rhododendrons that look normal as you may see them during any time of the year. When the temperatures rise after an extended period and you begin to notice that the leaves curl and look a little like a stick. We may see some of this rolling this coming week. What is going on is that the leaf is trying to transpire and bring the water up from its roots and leave through the pores or stomas. Only problem is that when the ground is frozen the plant can’t perform as it normally would and that is the azalea’s normal reaction to the transpiration process. One cure for this problem would be to have watered the plants heavily before the current weather started. The rhododendrons and azaleas that have leaves on during the winter will have this stick appearance and is considered a normal reaction. This normal stick appearance reaction can be an extra stress on a plant that you’ve just planted and putting this compound on the surface of the leaves you can give your plant an extra chance at survival. You would only want to apply this material before you would begin to experience freezing temperatures. If you put this compound on the plant too early it may create other problems. We want to continue to allow the Carbon dioxide uptake of the rhododendron or azalea, which a part of the normal functioning of the plant and the water vapor is retained in the plant. Therefore gases can exit the leaf and the water stays. All that I could recommend for your azalea is that if your plant does not lose any of its leaves during the winter, then it makes a lot of sense to get the anti-transpirant or anti-desiccant.
A simple recipe for an anti-desiccant is one drop of pine oil for each quart of water. Mix the pine oil with the water and pour in the sprayer. This compound is to be sprayed on the top and bottom of the rhododendron leaves providing the protection.
I hope that you all watered your plants over the drought periods we had this year. My normal recommendation for watering any plant is that you should have at least 1” of moist soil down from the surface of the ground near the plant. If you can put your finger into the soil and the soil is moist 1” down all around under the drip line of the tree you should be set for a plant that has just been in the ground for 5 years. This process should be done about once a week during the dry weeks. For a new evergreen planted within 5 years the process is a little different. You should stretch out that perimeter another 3-5’ and beyond and the moisture should go down 12”. This should be done a minimum of 3 times during the month as the drought continues. I’ve also been taught that if you water your azalea or rhododendron well before the ground freezes your plants will also have an improved chance to survive.
What kind of perked me up on my gray stroll through my garden were the tiny glimpses of color that invaded the gray. I’m enjoying the berries on my snowberry and beautyberry bushes. Hope you enjoy your stroll through your garden. If you have some questions about your garden please don’t hesitate in e-mailing me at firstname.lastname@example.org. You can find links to my columns and blogs on my website www.mikriscoop.com. I shall do my best in helping you through the problem.