More On Pruning

This hedge has everything going wrong.  More than likely, it gets topped every year with an electric hedge clipper.  The work goes fast, and the result makes me cringe.  Repeated cuts into the top layer has resulted in so many branch breaks that the resulting dense top layer of foliage forms an impenatrable barrier to light to the interior of the shrub.  This hedge is mostly sticks, all year round.  Pruning branches individually takes a lot more time, but the time it takes is worth it.  Sometimes I describe pruning as a haircut-specifically, a shag haircut.  The branches on top are short and shaggy; the upper side branches are headed back slightly to allow light to get all the way to the bottom.   

The early season look of this hedge is ample evidence that skirting up a shrub is a bad idea.  In an effort to keep the sides of the shrub perfectly vertical, all those stray side branches have been pruned off. Not so clear from this picture is that the hedge had been planted so close to the driveway that any side branches would impinge on that hard surface.  This hedge in its natural state would be 4 times as wide, and beautiful.  A skirted shrub is all legs, with little tufts of green on the top.  Naturally, carefully consider placement before you plant. 

This lilac hedge is wedged between two driveways. There really isn’t room between the drives for any plant that I know of, even though the screen is welcome to both neighboring parties.  To make the best of a bad situation, regularly removing the largest stem to the ground every year will encourage the lilac to sprout from the ground level.  This keeps the green coming from below. This hedge has a decidedly layered look.  A lower layer of green, then a taller layer of sticks, then another layer of green. This striping is very evident in early spring. Its clear these lilaces were pruned across the top, all the same height, on repeated occasions.  Pruning branches irregularly, at all different heights, encourages green all over.  Only a few plants can be pruned into boxes and globes, or balloons.   Balloon bushes are those skirted up stick shrubs with balls of green at the top; they look like a hot air balloon, only not as pretty.  This is a particularly displeasing look, as it bears no remote resemblance to any plant’s real habit of growth.

These hydrangeas have been pruned back to a few main trunks.  Though the look is sparse, there is little to fear.  Limelights bloom on new wood.  They do not bloom until July in my zone.  There is plenty of time for this shrub to grow and put out flowers.  Cutting back to these main trunks in the spring keeps the shrb in scale with the allocated space in a natural way.  Letting pruning go for too long only makes your shrub renovation look even more extreme.

Hydrangeas grow fast.  This bleak look lasts for only a short time in the spring.

I prune my own hydrangeas to a roughly symmetrical height, first.  Mine are grown in blocks, not rows; they make a substantial mass when they bloom.  They are also tucked behind a Hicks yew hedge; I need every inch of height I can get out of my hydrangeas so I can see their flowers from the street.  Pruning should be done with a particular end result in mind.  I do not prune my hydrangeas any lower than 30″ overall, as I like their height.  

Once I have pruned down to the height I like, I then prune out crossing branches.  I may prune out the center of the shrub if I think it has gotten too dense. I leave the outside branches alone. There might be some vague resemblance to an egg laid on its side, with holes in the top-when I am done pruning.  

It is easy to see that this single old calloused cut from last spring resulted in three new branches.  Pruning is not the end of something-it is the start of something bigger.  These three branches from last year, located in the center of the shrub, I have pruned back hard. I like to avoid long runs of woody branches-as I do not like hydrangea plants that droop.  A sturdily branched undercarriage makes for a strong and weather tolerant shrub. 

This bed of hydrangeas belongs to a client.  They face down an old stone wall which is but four feet tall. She cuts them back very hard-to within 14 inches of the ground.  She has in mind to keep the flowers at about the same height as the wall.  Pruning hard keeps the eventual plant height in bounds.  

In bounds, but blooming beautifully; this I like.

Let’s Talk Pruning

Were I ever to be appointed garden czar, I would require a certificate in proper pruning before I would ever sell a pair of pruners to anyone interested in growing plants.  OK, just kidding. This is the USA, and everyone’s freedom to prune as they see fit is guarenteed by the constitution. But I do see lots of evidence of uninformed pruning, so I thought it might be a good idea to offer some pointers; does this sound more friendly?

 Plants have a natural habit of growth.  Anyone interested in plant habit has no end of sources to research this subject.  Plant tags give this information at no extra cost.  Where people get into trouble is placing a plant they like in the wrong place. Shrubs that mature at 8′ by 8′ have no business being planted next to the sidewalk.  Planting two giant shrubs closely on either side of a walk that with true and brave pruning that results in an arch overhead-brilliant. The single shrub placed properly for the pot size, and not the mature size, will grow into a pruning nightmare. The pruning required to correct a mistake will make you look like a dictator-not a gardener.

The appearance of a large growing shrub planted in a too small a space, that has been pruned back to fit that arbitrary space, will offend the eye.  Pruning is about giving every branch light and air; pruning is about keeping a shrub green and thriving top to bottom.  Pruning is not about wedging a plant into a space that nature never intended. Any plant, given the time, space and care to mature to its finest form-glorious. 

        Woody flowering shrubs have a specific period of bloom-nothing tricky here.  Prune promptly after the bloom. I am talking forsythia, lilac, rhodendron, roses, and the like. Every pruning cut encourages a plant to send out multiple shoots from the cut. The best time of the year to see how one cut produces multiple shoots is right now.  There is not much foliage yet to obscure how a plant is responding to your pruning.  Get out in your garden, and study the pattern of the sticks-the results of your pruning. 

 Woody deciduous shrubs have a natural habit that provides no end of clues about how to properly prune. Euonymus compactus alata-dwarf burning bush, grows strongly to 8 feet high, and as wide. The yews pictured above are some form of taxus densiformis.  Their natural form is loose and sprawly. Should you be pruning in a box or ball shape 4 by 4 feet-there is conflict sure to come. Each cut brings forth a proliferation of new growth.  Sooner or later the growth on the skin of this yew will be so dense, all the foliage on the interior will languish and finally die from lack of light.  Though closely trimmed yews can be very pretty, I try to cut a few light holes in various spots-I call this swiss-cheesing the plant.  Let some light reach the interior.  These yews are placed such that should they get bigger and bigger, they will not obstruct a walk. Yews cut back to bare wood will sprout again-but the recovery will be slow. 

 Once hydrangea buds show green, I prune.  Annabelle I never prune hard.  Like a tea rose, a hard pruned Annabelle will reward you with fewer, and even more giant ball shaped blooms.  As this shrub has weak stems, and goes over in the first hard rain after blooming-there is no need to exascerbate its shortcomings. Those giant balls on the ground in the mud-not so satisfying. Prune lightly, and all over.  Every branch; take the time to cut them so they have a little sun and air space all their own. Your patience will be rewarded with lots of a little bit smaller blooms-making the entire shrub more weather resistant. 

There are those yards where I see everything pruned into a green meatballs, green boxes, mushrooms, or rectangles. Or some lopsided version of the above. Should it be your idea to prune towards a geometric shape, get out the level lines and do it right.  Imposing mathematical geometry on a natural form needs to be done with knowledge aforethought.  And purpose. And most importantly-the right plant. Some plants respond and thrive in response to this treatment.  Other plants respond by throwing a skin of leaves-the interior branches go dead from lack of light.  Boxwood tolerates this type of treatment; other plants-not so much.

 No plant needs a heavy hand.  Heavy hands come from those non-gardening people who have been given the chore to get the yard in shape.  Heavy hands given a sharp instrument-not always the best result.  I think about every cut.  I cut with a natural form in mind.  I cut to help provide air, light, and densely natural shape. There are those for whom this statement is an utter bore-but if you garden with a passion, you know exactly what I mean.  

Prune with sharp and clean clips.  It is no good to spread communicable trouble around with dirty and infected clips.  Clip what needs be clipped-pass on what does not. Stop the pruning in midstream, and consult-should you have any questions.  Poor pruning is not the end of the world; plants have an incredibly strong instinct to survive.  They will endure, and possibly outlast you. But the season comes but once a year. 

Stay tuned.  More on proper pruning to come.