Mowing hardy bamboo groundcovers?

[Snowbird]

I've seen where most people in my zone tend to mow their bamboo gc's down in the fall or spring. i assume this is to provide room for new growth. so, here are the questions:

is this necessary with newer plantings?

would it be more beneficial to have leaves on the culms for an added boost of energy during shooting season?

is it possible that people are mowing them down to prevent topkill?
and would that prevent the growth of the plant in any way?

[Mark Meckes]

Hi Seth,
A well established groundcover bamboo can be mowed or clipped down to near ground level in early spring and it will produce a vibrant flush of new growth.
Though it may not grow as tall if done this way, the resulting growth can be much fresher looking with denser growth.

With a new planting, I would suggest waiting till spring to see how much live tops there are and snip out any dead portions with a hand pruner.
If your planting has a good base of rhizomes, you can choose either way, depending on the effect you desire with the planting.

Most groundcover bamboos though not tall growing, make up for it by having very vigorous rhizomes.

I have spent many hours meticulously snipping away old dead parts of small bamboos ... and as the years progressed and the planting spread, I would resort to clipping it to ground level with a hedge clipper in the planting foreground, and letting it grow taller in the background if it had sufficient green tops.
Again it all depends on the affects you're after and how much time you have on your hands.

In very cold climates, in some years harsh winters will zap all the top growth on more than just ground cover bamboo, and will also require other medium height and taller bamboos to be cut back to the ground.
Sometimes this will cause some taller bamboo to behave like lower growing bamboos.
In these cases when the culms may or may not re-leaf, I would only hand remove any culms or portions that had desiccated to a beige color, and wait for final pruning until after new growth arrived.
As many culm parts can still retain some green nutrients, I've preferred to keep those live portions intact till after the new shoots arrive before removing them, with the belief that they would divert some energy to the new growth.

Ground cover bamboos also have varying degrees of hardiness in cold climates.

Sasella masamuneana 'Albostriata', has tough leathery leaves and is quite hardy and reasonably evergreen if provided snowcover.

http://www.bamboocraft.net/bamboo/data/627/thumbs/SmalboFRPA1994-001.jpg (http://www.bamboocraft.net/bamboo/showphoto.php?photo=3473)
This bamboo used to grow to about 3ft (1M) tall for me in NE Pennsylvania, a very vigorous bamboo.
Here in central Texas it wimpers along, barely rising more than a foot tall - can't take the heat.

Pleioblastus viridistriatus has soft textured leaves and would always act like a deciduous plant in cold climates, losing almost all it's leaves, regardless of the winter severity.
Here's a 100+year old planting (planted 1890's) at the Arnold Arboretum in Boston Massachusetts:
http://www.bamboocraft.net/bamboo/data/592/thumbs/PlvirAAMA9008-002.jpg (http://www.bamboocraft.net/bamboo/showphoto.php?photo=3402) Summer

http://www.bamboocraft.net/bamboo/data/592/thumbs/PlvirAAMA8903-001.jpg (http://www.bamboocraft.net/bamboo/showphoto.php?photo=3407) Late winter

New growth of Pleioblastus viridistriatus emerging in spring, after dead growth was mowed down.
http://www.bamboocraft.net/bamboo/data/592/thumbs/PlvirAAMA9005-001.jpg (http://www.bamboocraft.net/bamboo/showphoto.php?photo=3404)

Mark

[Snowbird]

thanks mark. :)