Tuesday, March 24, 2015

Are you cruel enough to be a gardener?

For the past four years, I have kept a close eye on Miss Lawrence's Camellia sasanqua hedge at the sidewalk. It was not uncommon to see evidence of scale in the hedge, which had been kept sheared. Scale is an insect pest that feeds on plants by piercing plant tissue and sucking sap... literally sucking the life out of a plant. All kinds of scale like close, dark, humid quarters. In an effort to create a less hospitable environment for it, I thinned out some of the densest parts of the hedge last year. The intention was to increase air circulation and light.  While performing an annual plant assessment this winter, I realized that the scale infestation was quite severe. This was confirmed by local experts and members of my garden committee, as well as my gardening colleagues, Ben, Damou, and Danny, who have been battling scale on the oldest camellias in the Clarkson Garden.

During the process of educating myself on these nasty little vampiric creatures, I learned that there are several different species - most of which were attacking the hedge. Most were on the undersides of the leaves, but a lot were also on the limbs. Not good. Some species of scale are "easier" to control than others, but none are exactly "easy" to completely eradicate. So what does one do in a case like this?
Scale on the undersides of the leaves...
...and on the limbs.  Yuck.
The most important thing: do whatever I can to keep existing plants happy and healthy.  I weighed all of my options, keeping firmly in mind that many of the plants in the hedge are nearly 70 years old. Behind door number one, the less radical treatment - a regimen of chemical drenches, periodic spraying and pruning - over the course of years - which may or may not be completely effective in the end. (Ugh) Behind door number two, the more radical approach - renovate the hedge by pruning it way back, giving it a chance to regenerate with clean, healthy foliage that can be strategically pruned as it grows. (Seems drastic) And finally, behind door number three, the most radical approach - completely remove the existing hedge and start over. (Can you say "last resort"?)

It wasn't an easy decision, but the best option - and definitely most environmentally-friendly - was behind door number two: rejuvenation pruning... or, as I like to think of it, pressing the "reset" button.  Older plants usually respond better to hard pruning; they have well-established root systems that enable quicker regeneration. Plant maturity is definitely on my side for this one!

So Ben, Damou, Danny and I set to work, and in one afternoon, completed the first pass.  It's best to start off a pruning project like this by being a bit conservative with your cuts... you can always prune off more later. And I did.

After the first pass of rejuvenation pruning
Rejuvenation pruning complete!
Sometimes older gardens present difficult situations.  Hard decisions must be made.  Such was the case with the sudden death of most of Miss Lawrence's witch hazel, Hamamelis intermedia 'Jelena', which required the same type of severe pruning.  Thankfully, that turned out to be a success story.  I remain ever-hopeful (crossing my fingers, toes, and nose hairs) that rejuvenating Miss Lawrence's Camellia sasanqua hedge will reap similar results.  I suppose I am, after all, cruel enough to be a gardener.