The Basics of Trimming

The other day I stumbled upon an infomercial for a new product called the "Garden Groom".  This is a compact unit with an enclosed blade designed, supposedly, to trim your shrubs and hedges with a minimum of work and effort.  I will admit the attached basin designed to mulch the branches it collects makes it appear to be a good idea, you can either empty the basin into a leaf bag or onto areas needing mulch, saving one more step in your trimming process.  However, despite how "easy" the infomercial makes it seem to shape a shrub, it violates everything that you really should do when trimming a shrub, and doesn't really work as described (at least according to the online reviews).  In fact, while watching the infomercial I found myself getting a little irritated.

Why irritated?  Because shrubs and hedges will not thrive over the years being trimmed only on the surface.  When you only cut the top growth on a shrub (like a yew or a holly) you spark that limb to branch out with new growth.  Then the next year you trim those new branches and then those branch out, too.  Over the years, you end up with an overly thick green surface on your shrub with all dead wood underneath.  Air needs to circulate within the main branches of your shrubs and water needs to get to the roots.  The best course of action is to thin your shrubs and hedges.  My sister uses the "keep it simple" theory.  That is, uncomplicate your shrub.  Take out any branches that cross each other, trim back any branches that are dead or dying, and reduce your shrub to several strong main branches especially if you expect the shrub to grow quite large (like a hydrangea, rhododendron, and so forth).

Please be careful to time the trimming of your shrubs so that you don't loose this (or next) year's  blooms.  For example, I always trim my hydrangea in the Spring before it begins to leaf out.  As I recall, a hydrangea is like a weigela, blooms only on new growth so it's better to cut back the older limbs when shaping the shrub.  For Spring blooming shrubs, like rhododendrons, it's best to cut it back once it's done blooming.  If you do it in the Spring, like your hydrangea, you will actually be cutting off those branches that would be producing the blooms.  If you must cut a significant amount of your shrub back due to a long period of over growth, be prepared to have a couple of lean years of blossoms before the shrub fully recovers.  For old lilacs, you can cut up to a third of the shrub back without harming it, but other shrubs, like a spirea, you can almost cut it to the ground with no repercussions; it's best to check a gardening resource (like a local nursery) if you are unsure.

This is a dwarf Hinoki False Cypress

This is a Boulevard False Cypress

Some evergreens, like false cypress, mugo pines, and arborvitae, need no trimming at all (and do not lose leaves in Fall).  If you would like to keep your yard work to a minimum, consider planting evergreens as opposed to blooming shrubs. Just be sure that you give your shrub plenty of room to grow especially if you will not be trimming it back.  I've since moved the autumn joy sedum seen behind the Hinoki False Cypress as the two were too close together.  Another nice thing about these false cypress, is that they grow quickly.  We could only afford to purchase very young specimens and at first, we thought it would take a long time for them to mature, but we've had each only a few years (maybe 6?) and they really look beautiful.  The Hinoki has also been moved three times in the yard until I finally settled on its perfect spot and it has forgiven me each time.  (I first had it in the front like the Boulevard but the snow and ice that landed on it from the roof caused trunk to split.  I cut out the broken limbs, and it grew right back into the space.)

Overcrowding Revisited

Overcrowding your yard is so tempting when you are first planting trees, shrubs, and perennials.  You look at your yard and want that instant gratification of seeing masses of color and texture.  DO YOURSELF A FAVOR - RESIST! There are three stages of perennials (according to gardening lore): sleep, creep, and leap. Remember this when you feel impatient.  If you over crowd you'll spend those "leaping" years moving, rearranging, and perhaps tossing a lot of plants.

Not that you won't ever have to move things around even if you are careful in your placement.  Currently I am considering whether to find new homes for a dozen or so yellow siberian iris (not my favorite as they bloom only halfway up the stem unlike my purple who blooms are so elegantly perches atop theirs), some purple cone flowers (aren't blooming as I thought they would in a mildly shady area, plus getting overwhelmed by a maturing holly bush), some daylilies, and a gigantic misplaced hosta that I thought would just be smaller. It is usually best to move and rearrange your yard in spring and fall when the plants are either going into dormancy or just coming out.  I will probably ignore that rule this summer as I'm afraid with all those leaves to be raked in the fall I won't have time.  So, for those plants that have already bloomed (iris and lilies) I will go ahead and move them.  I will also be certain to water frequently until winter to make sure their chances of surviving my impatience are greater.