Several weeks ago you recommended 'Kwanzan' cherry as an "excellent street tree," but the cherry trees in our neighborhood look terrible. Why do you recommend this tree?
Perhaps I should dampen my zeal for the 'Kwanzan' cherry. It is prone to disease and insect damage and the trunk seems to be especially vulnerable to damage from string trimmers and lawn mowers. I have seen some outstanding trees ruined when the bark was inadvertently struck by mowing equipment. It caused the trees to form large cankers and then decline.
On the other hand, if you are looking for a small street tree that will grow underneath power lines, there are few other good choices. Native trees like dogwood, redbud, hawthorn, and serviceberry are certainly not suitable as street trees, and other small exotic trees have their share of problems.
We ask an awful lot of a street tree. It must stay small and grow under power lines, but also be highly branched so that pedestrians and vehicles can pass underneath it. It must tolerate awful growing conditions, including pollution and poor, inadequate soil. It must be a clean tree that does not produce branch and fruit litter. And it must thrive in neglect. After the initial planting, street trees get very little help. It is hard to find a tree like that.
I planted a mass of ferns in a shaded spot of our rowhouse last spring. They are evergreen ferns and were beautiful until the ice and snow smashed them. Should I cut them back to the ground now?
Yes, you could certainly cut them back. It will not harm the plants. However, you could save yourself some work and just let them lie on the ground. The old fronds will likely die off in the summer and become mulch for the ground. In the meantime, new fronds will emerge from the crown to produce a full bushy plant and cover over the old fronds. If you decide to cut them back, I would do it relatively soon. It will be easier to do before new fronds emerge.
1. This is a great time to cut back perennials and do a thorough yard cleanup. It is best to do this before spring flowers and bulbs emerge.
2. Get your mulching done before the mad rush of spring. If you order mulch and spread it now, you will have a mundane project out of the way and can enjoy planting new trees, shrubs and flowers this spring.
Dennis Bishop is an urban horticulture educator for the Baltimore office of the Maryland Cooperative Extension Services. If you have a gardening or pest problem, you can call the Home and Garden Information Center hot line (Monday through Friday, 8 a.m. to 1 p.m.) at 800-342-2507. You can also e-mail questions, order publications and diagnose plant problems by visiting the Web site www.hgic.umd.edu.