October 21, 2018
I decided not to use rhizome barrier on my bamboos and rather risk breaking my back twice a year doing some rhizome pruning. So far, it was not an issue and bamboos failed to take over the garden. So far. This year, weather was ideal for bamboos to grow rapidly above and under the soil level which made regular maintenance a bit more labor intensive.
Summer rhizome removal
Summer started later than usual and temperatures were not as high as they could +have been. After the first part of our growing season, I decided to remove the escaping runners and make it easier to complete the cleen-up in the fall. The first time I dug around my bamboos this year, there were only short rhizome escapees, mostly on Phyllosttachys aureosulcata ‘Spectabilis’ and Phyllostachys pubescens ‘Moso’ seedling. Hibanobambusa tranquillans ‘Shiroshima’ had runners all over the place, but they rarely go deep enough to cause a problem. To fight the Shiroshima I dug a trench around it, which saved me from autumn pruning. I just snapped the runners as they emerged in the trench. All runners were easy to remove because they didn’t get established yet and had only minimal amount of roots. The issue, however, was the dry clay called soil and heat during the day.
The pruning fiesta
As the weather started to cool down significantly, I started the final rhizome cleen-up this season. Soil is now moist, not overly wet and easy to work with. The rhizomes and roots, however, are not. P. aureosulcata ‘Spectabilis’ was as good as it gets. Almost no spread into unwanted direction into the lawn. I was done with it in no-time. Then it was time to make sure I check on my overly aggressive P. pubescens seedling. The first swing I made with the pickaxe had informed me about what lies below the soil. In only a couple of months, relatively small bamboo managed to grow numerous runners in all directions. They were already well rooted and branched out, which made them hard to get out of the soil. Luckily the soil was moist enough, if it would be just a bit drier, I would not have been done yet – yet, my back would be.
I wanted to make a bunch of new bamboo plants this year and plant the rhizome divisions. When I saw how many there are, I just started tossing them away. Divisions will have to wait for a day when I feel less lazy. Maybe next fall.