IN THE GARDEN

By Doreen Trudel

After yet another month of snow and cold winds my garden is looking bleak. Some of my shrubs such as my small leafed azaleas and hebes survived the first blast of cold but they are now looking pretty ragged.
I have started to look at gardens around Point Roberts to see which shrubs seem intact after each storm. Any species in good condition goes on my list of potential replacements for shrubs that I have lost to the winter weather.

Some of my survivors were acuba, choisya, Viburnam Davidii, Philadelphus and both Osmanthus delavayi and O. heterophyllus. There are other shrubs that will just need some pruning and extra care. It is no surprise that the conifers survived the best so I will be adding many more varieties this spring.

In between the snow storms we built a 45-foot pergola on which to grow grapes so I have been researching grape varieties that grow well in our climate. Not only will I eventually be able to enjoy a sweet crop but the vines will provide some colorful shade on a hot summer’s day.
Grapes require a warm, dry environment. Our maritime climate encourages rot and mildew, two serious grape vine problems. There are a few varieties which have been grown successfully in the Pacific Northwest and if our summers continue to be warm and dry we may have a greater selection from which to choose.

Growing grapes is a science and I am not an expert but here is some background information to think about if you are interested in growing grapes. To decide if a particular area or region can potentially grow grapes a heat unit number is determined based on temperatures, annual rainfall, length of days and elevation, among other factors.

Extra heat units are given for specific site conditions such as south facing slopes, rocky soil or windbreaks. Anything that makes your site warmer increases its potential as a vineyard. From a chart on the internet I located Bellingham’s heat unit number as 1321. My vines will grow on a bit of a south slope in rocky soil in a generally warm area so I am hoping I can add some heat units to my site calculation.

To give you an idea what the heat units mean, it generally takes 2000 units to reliably grow most wine grapes but having said that some European vineyards are in areas of 1700 units or less. Various grapes need differing amounts of heat to ripen so it is important to choose varieties which have been developed to grow in our cooler climate. Very early (VE) cultivars can ripen more quickly in areas of less that 1500 heat units while early (E) or midseason (M) cultivars need a site with at least 1700 heat units. The Washington State University Cooperative Extension website has detailed charts, variety lists and lots of information on viticulture in our area.

It is not too late to order or buy vines to be planted in mid-February. To choose which varieties to plant you must first decide how you will use the fruit. An excellent source for grapevines is Raintree Nursery in Morton, WA. They have an informative catalogue and website and a helpful horticulturalist. Raintree offers almost 50 varieties of wine, table and juice grapes. I chose Venus, Mars, Interlaken, Lakemont and Neptune, all table grapes with consistent success and disease resistance in our climate.

Grape vines are self-pollinating. They need full sun, deep well-drained acidic soil. Planting in rich soil encourages excess vegetative growth so a lighter soil is a benefit in this instance. The key is to provide the vines with as much sun as possible and keeping the roots warm. Mulching with stones or a dark material might retain a bit more heat. The vine will need support and pruning but once established, grapevines can live for many decades. Two inexpensive and helpful booklets are Maritime Grape Growing and Great Grapes both available from Raintree.

It is difficult to write in much detail about pruning without illustrations but again, Washington State University’s website has clear and concise diagrams and information. I know several people in our area who grow grapes so I look forward to many alfresco summer meals under my grape arbor.

This year’s Point Roberts garden tour will be held on July 8 so mark your calendars now. Don’t forget to attend the Point Roberts Garden Club meeting February 3 at 9:30 a.m. in the community center. They have some exciting community projects planned and more members are always welcome.