Saturday, July 26, 2008

Trucks Cause Junipers' Woes

By Tracey Hobson
Of the Journal
      Q: We have several large upright junipers planted next to our driveway. Over the past few years, they seem to be in a state of decline. They aren't as robust as they once were. I can't find any bugs or troubles at all on the trees. Do you have any suggestions as to the cause of their decline?
    A: The trees in question were close to me so I stopped by to look. The owner was right in the fact that no pests could be found, and there were several other trees in the same stand that weren't showing the same symptoms.
    As we stood looking at the trees, her husband pulled up and right behind him a couple of other vehicles parked very close to the three trees that were "in a state of decline."
    Ding, ding, ding! Of course! As simple as it sounded, I believe that it is the trucks. About three years ago, they had changed "traffic patterns" in the back yard. Now the area beneath the trees was hard-packed and looked paved! The roots of the declining trees are effectively being suffocated. Because these vehicles, weighing a ton or more each, had started to park in that space, the soil which is naturally heavy anyway, compacted to the point that the trees aren't able to breathe!
    Looking amazed, the tree owners have since decided to stop parking so close to the trees.
    I also recommended trying to rough up the soil under the trees to re-oxygenate it, creating a moat system as wide as the "drip line" and working in some gypsum to help un-plate the soil. The roughing up of the soil being paramount to the health of the trees, I cautioned the owners about tilling too deep, too quickly as the tree roots had probably come up, so to speak, trying to offset the compaction, and they didn't want to ruin any of the suffering trees' roots.
    In the spring, they could apply a "soil rejuvenator" (like the product "Revive") to continue the process of making the soil healthy around those trees.
    Watering was discussed, too. Now it will be up to the care given by the owners and Mother Nature as to whether or not the trees make it. I couldn't say if the trees were too far gone or not, and time will tell if the years of compaction could be reversed.
    Q: I noticed a large shrub outside a grocery store in one of the planters and it is beautiful! Right now, it's full of dark purple blooms. I don't think it's a Russian Sage. Can you tell me about this shrub?
    A: If my guess is right you are noticing a plant called vitex or chaste tree, and you are right, the blooms the shrub is wearing this time of year are just fantastic! The vitex can grow to a height of 12 feet with no problem.
    What I really like about the vitex is its "formability." You can shape and prune the vitex to look either very full or rather manicured.
    The vitex is a great patio grower as it can be trained to not take up a lot of room. Usually the plant is offered in the market as a multitrunked individual, but you can at times find it as a single trunk specimen.
    The foliage is a cool gray-green color on a rather pointy-shaped leaf. It's also usually darker on top than underneath. That gives the vitex a sort of shimmery look when the breezes blow.
    The flower spikes produced in the heat of the year can range from a light lavender to the darkest purple-blue you will ever see in the plant kingdom. They are so easy to grow in these parts, and they aren't known for any major pest troubles, either.
    Another attractive thing about the vitex is the scent of the foliage if it gets rumpled. It's an astringently clean smell that I'm truly fond of.
    So go out and find a vitex to pet and see if you can make room for one in your landscapes.
    Happy Diggin' In!
    Need tips on growing your garden? How much to water those bushes? How to transplant a tree? Tracey Hobson is a certified nurseryman. Send your garden-related questions to Digging In, West Side Journal, P.O. Drawer J, Albuquerque, NM 87103.
   

---