Q I planted male and female kiwi plants years ago. There has been terrific growth but no fruit. Do I have to do anything special to get fruit? Is it all right to trim the vines?
A Heavy fruit production is typically elusive with hardy kiwis. They need a site in full sun but protected from chilling winds and away from frost pockets because they break dormancy early in the spring and are damaged by late frosts.
Like grapevines, pruning is key to fruitfulness. If you were starting anew, you would allow a main trunk to grow vertically on the arbor, spreading out to two horizontal leaders. Don't allow these primary branches to twist around the arbor in order to keep future pruning simple.
The annual pruning regime consists of trimming back the leaders and thinning out the lateral shoots that grow on them. The shoots you leave should be cut back to eight buds now. These shoots will bear fruit this year. The oldest fruiting shoots should be removed each winter. Train the male vines the same way to maximize flower and pollen production. One male is enough to pollinate up to eight female plants.
There are two basic species of hardy kiwi. Actinidia kolomitka is quite ornamental with its white and pink spring growth, but it is not as productive as Actinidia arguta, which is the kind most commonly grown. Several cultivars are available. Issai has long been touted as one of the best because it is a self-pollinator. Unlike all the other kiwi clan, its flowers have both male and female parts. However, it is not productive on its own and is a better fruit if grown with a male pollinator.
We are moving to another property in a few weeks and want to take some perennials from our current garden with us, including anemone and phlox. What is the best way to dig, transport and store until I'm able to plant in spring? We will be at a higher elevation and it is likely spring will come a bit later than the D.C. area.
If the soil is not frozen, dig the anemones and phlox with a garden fork and transfer them to the plastic trays available from nurseries. Mulch them heavily with leaves or straw. Do this even if you are digging them just a few days before your move. If you don't, rapid temperature changes could cause the roots to dry out with fatal results.
In your new garden, have a bed ready to receive them, even if it is just a temporary one. If there is a plot for vegetables or a bed for annuals at your new home, this may be the perfect location to hold them over while you work on creating and improving permanent perennial beds. They can be held for several months, and planted in the fall if necessary.
Not all perennials accept a move like this with grace. Those that are only barely hardy in our area may not accept the colder winters in your new garden. Some perennials that revel in the heat of Washington summers, such as marsh mallow, may not appreciate the cool mountain summers. If you are not in deer territory now, but are moving to one, that is another consideration, especially for deer candy such as roses and azaleas.
My 40-year-old climbing roses grow against our two-story house. The upper floor has siding that is scheduled to be replaced in a renovation project. Can we prune the roses severely and save them? My son has suggested simply cutting the trunks where they meet the siding.
If the roses were younger, you could do their winter pruning now and at renovation time untie the upper branches and allow them to flop back from the house. I suspect your branches are so old and thick, though, that they will not bend back. If that's the case, take a deep breath and cut them back to about a foot from the ground. New, vigorous canes will emerge this spring. Just before the renovation project begins, pull the canes to the side and secure them on the ground for the duration of the work. Scrap pieces of lumber or pieces of firewood may be used to hold the canes close to the ground.
Scott Aker is a horticulturist at the U.S. National Arboretum.
Have a question about gardening? Write Digging In, Home Section, The Washington Post, 1150 15th St. NW, Washington, D.C. 20071; fax 202-334-5059 or e-mail home@washpost.com.
