September 20, 2007 at 8:06 a.m.
If you are planning to start a raspberry patch or plant blueberry bushes, there is plenty of work to be done, now. The average gardener, (this includes me) doesn't give enough attention to planning for what we are going to plant. This is the ideal time to prepare for your raspberries or blueberries. Both need a sunny well drained area. When I first became interested in blueberries, I thought that since you pick wild berries in the woods, they need a shady area. If you have ever picked wild berries, you would know that you find the wild berries in a clearing.
Raspberries need good soil, especially at planting time. About 90 percent of the root system is in the top 20 inches of soil where the root must take up moisture and nutrients. They will not tolerate poorly drained soil. They also require full exposure to sunlight and air movement.
Most of us don't have full control of the site, but if you do, I have a couple of suggestions from my own experience. Planting in an established garden has the advantage of weed control and soil that has been worked for some time.
But, previously grown crops may have some pathogens and diseases that can build up in the soil and affect the raspberries. Verticillium wilt and anthracnose (fungus) can be in the soil where tomatoes, potatoes, egg plant, strawberries, etc have been grown.
I have two different areas where I raise raspberries. One is in my regular garden and the other patch is just raspberries, I have noticed that the yellow jackets are much more destructive in the fall in the garden patch. I suspect it is because the over ripe fruits and vegetables from the garden attract the yellow jackets and they go from my garden to my raspberries.
Another suggestion is to avoid having raspberries next to a field where soybeans are grown. During the growing season the Asian beetles are feeding on the aphids on the soybeans. About the time the soybeans ripen is the same time the fall raspberries and grapes ripen. They move from the soybeans to the grapes and raspberries and can be a real problem.
Once you have selected a site the next very important task is to have the soil tested. You can get a soil test kit from us at the Extension Office in North Branch. This should be done as soon as possible so the soil can be amended yet this fall. Raspberries prefer a soil pH of approximately 6.5. Often the pH is outside the desired range of optimal growth, so lime or sulfur may be applied to modify the pH. Lime is applied to increase soil pH, sulfur is applied to decrease pH. It takes about a year for the soil to change significantly.
There is nothing that destroys your confidence or crop as much as weeds. I suggest that you apply Round-up on your selected area at a rate of six ounces per gallon. Apply it on a warm sunny day as it is most effective at temperatures of at least 70 degrees. Give it time to do its work. Although you can see the result in a day or two, it takes about 10 days to complete the task.
After the weeds are dead it would be a good idea to work up the ground. Both my raspberries and blueberries are planted in rows that are about three feet wide with eight feet of grass between each row. The reason for this is that if there is too much fresh dirt it will splash up and dirty the fruit and dirt on the leaves invites disease.
Everything I have written about for raspberries is also true for blueberries, except for the fertilizer. Blueberries need an acid soil with a pH between 4.5 to 5.5 pH. The time to amend the soil for blueberries is next spring when they are planted.
Many of you are aware that the Chisago County Master Gardeners sell bare root raspberries, grapes, asparagus, onions and native plants. The proceeds help pay for the speakers for our classes we offer. We have more than 600 gardeners on our mailing list when we send out information on upcoming classes and ordering bare root plants. We also have classes that share information on all the plants we sell. If you want to get on our mailing list call the Extension Office at (651)674-4417.
PLANT CLINICS: The Monday night plant clinics at the office are done for this year, but you can still talk to a Volunteer Master Gardener at the Lindstrom Farmer's Market, Saturdays from 8 a.m.-noon on Highway 8 in the St. Bridget's Catholic Church parking lot.
Please note: there is no longer staff at the North Branch Office who can answer gardening questions.
VOICE MAIL: You can leave a question for a volunteer Master Gardener at 651-674-4417. Depending on the volume of calls, they try to respond within a couple of days. During office hours ask for the Master Gardener voicemail, after hours, select ext. 18. You can also get your question answered on the web at: www.extension.umn.edu/askmg
UPCOMING CLASSES: Join the Master Gardeners Tuesday, Sept. 25 at 6:30 p.m. for a class on Fall Lawn Care, presented by Master Gardener Donna Tatting. This class will give an overview of basic lawn care practices for all seasons with an emphasis on fall lawn care. We will also discuss lawn care practices that help protect and insure the water quality of our nearby lakes and rivers. The class will be held at the Senior Center in North Branch. You can call 651-674-4417 for more info. This would also be a good opportunity for anyone thinking about becoming a Master Gardener to see what we do and get more information about the program.
A cutback in staffing has made it necessary for the Extension Office to limit hours of operation. We would suggest that you call ahead to verify that the office is open if you plan to stop by.