Last week gardening columnist Margaret Lauterbach wrote about grapes. The day after her column appeared, I received a notice from the Snake River Table Grape Growers Association about its annual Table Grape School in conjunction with the University of Idaho. If you're thinking about adding grapes to your garden or already grow table grapes, this class is for you.
The school is a daylong class held at Parma High School on Saturday, March 2. Cost is $35 and includes lunch. You'll need to register by calling Maurine Baucom at (208) 722-6701, ext. 228, or email email@example.com. She'll email a registration form and conference agenda to you.
The class starts with site selection and includes everything you'll need to know through harvesting. After lunch, the class breaks into two groups: commercial growers and backyard hobbyists. There are classes specific to the different needs of these two groups.
At 3:30, the groups will go to the University of Idaho Parma Research Station for hands-on pruning instruction. So come to class prepared to be outside in whatever weather the day brings. Bring garden gloves and sterilized pruners.
One of the things they don't go over in the class is how to root grapevine cuttings to make new plants. Grapevines make a wonderful gift for friends, family and neighbors.
Pruning is best done in mid- to late February in the Treasure Valley. Make a straight cut across the vine, leaving at least two buds on the vine. The part of the vine used for cuttings is the thickest part that was closest to the trunk; the thinner ends will be discarded. The best cuttings will be about the thickness of a pencil.
With the pruned-off vine in hand, cut off about a foot long piece of vine, cutting at an angle. Make sure there are at least three buds on the cutting. Lay the cutting aside. Where you made the angle cut on the pruned off vine, cut again straight across right next to the angle cut. The straight-across ends (the ends that were closest to the trunk of the plant) will be where the roots grow and the angle-cut ends will be the top of the new vine. Cut two or three cuttings from each pruning, then discard the rest of the pruned vine.
Dig a hole on the north side of the house a few inches deeper than the length of the cuttings (14 to 15 inches) and just wide enough to accommodate the cuttings (4 to 6 inches). Gather up the cuttings and tie them with a string or a long twist tie. If you're starting more than one variety, you'll need to mark them in some way so you don't lose track.
Put the cuttings in the hole with the angle-cut ends at the bottom of the hole. By placing the cuttings "upside down," a plant hormone called auxin will rise to the top as the cuttings rest underground. When the cutting is later planted with the straight cut under the soil, the auxin will cause roots to grow first, then the auxin will again rise in the cutting, causing leaves and branches to form.
Leave the cuttings underground for about six weeks. Then dig up the cuttings and pot them up with the straight cuts in the soil and the angle cuts pointing to the sky. Keep them watered well whether in pots or in the garden.
Once they leaf out, they're ready to give as gifts or to increase your own grape arbor.
If you have particular questions about gardening you'd like to see addressed in this column, send them to firstname.lastname@example.org.