Special to the Times/News

Think bio-control is a panacea for dealing with exotic/invasive bugs?

Check out the latest issue of the National Wildlife Federation online magazine article, "Good Bugs Gone Bad," at www.nwf.org/nationalwildlife/index.cfm?issueID=76.

Long-term research shows many of the bugs introduced to control exotic pests have become pests themselves - even ladybugs!

This article reminds us that the web of life is so complex and intertwined that messing with one link may result in serious unanticipated impacts elsewhere. For this reason, be careful with exotic species even as controls against other exotics.

Some may be benign but it's hard to know the ultimate outcome.

August 2 was National Night Out when local Block Watch groups hold street parties to "take back the neighborhood."

The Lazy Gardener was invited to one such event in the White Center/Westwood neighborhood between Burien and West Seattle. The bait was a tour of a home garden. You can always get the Lazy Gardener out by dangling a garden for review.

In a regular neighborhood of regular houses and regular people, the Sellars/Archer family has tended an urban homestead since the middle of the last century. In addition to ornamental shrubs and flowers is an extensive vegetable and fruit operation tucked into a deep double lot.

Marionberries, raspberries, tayberries, grapes and kiwi vines fill an area the size of a suburban backyard. The beans, peppers and other veggies were fairly popping out of the soil.

And the tomato vines are already drooping heavily with fruit due to a secret weapon: soil heating cables. Gardener Steve says the air temperature for a good tomato set doesn't matter much as long as the soil is warm. He must have something there because most of us are just seeing fruit set during the recent hot spell.

The Sellars/Archers barbecued bratwrst for the Block Watch guests, shared homemade cookies and jam with all the visitors and gave me a box of fresh-picked berries to take home.

Once again, regular people proved that gardeners are the nicest folks.

Q My early bearing raspberries did great this year but are beginning to wilt and turn brown. I've kept them watered and fertilized but they look like something is killing them. What's going on?

A Raspberries are one of the top small-scale agricultural crops in the Pacific Northwest, perfect for urban farmers. Western Oregon and Washington are the nation's top producers because the vines require a specific winter chill and mild spring weather to give best fruit set.

Unfortunately, our wet winters present some disease issues. According to the Oregon State University Extension Service, root rot is a major disease of raspberry in the Pacific Northwest. Species of the fungi Phytophthora survive in plant debris and spores may be moved long distances in contaminated soil. They are attracted to the fine roots where they attack and begin to rot the root system.

No Pacific Northwest red raspberry cultivar is very resistant, although some advanced breeding lines available to commercial growers may be more so. Varieties 'Chilliwack,' 'Meeker,' 'Sumner,' and 'Summit' are moderately resistant, so look for them when starting a new planting.

After hot, dry periods, older leaves may wither or become bronzed and scorched. Fruit stems usually are shortened and berries, if formed, remain small and often wither before ripening.

Once the root system begins deteriorating, new roots may arise from above decayed ones in summer. Plants may appear to recover, but new roots are often weak. The new roots in turn become infected during cold, wet weather the following fall and winter so that the plant progressively declines.

While there is no definitive treatment for raspberry root rot, good cultural and fertilizer practices can minimize infestation and prolong productivity. Keep the area clear of leaf debris and provide good drainage with raised beds, mounds or berms, sloping the soil away from plants.

Tightly pack the alleyways between rows to increase drainage during winter rains. Install drain tiles if necessary to remove excess water.

Prepare new planting beds by solar sterilization of the soil the year before inserting new canes. In late spring, cover the empty prepared bed with clear plastic and secure around the edges.

Leave the cover on through the summer. Solarization will heat the soil sufficiently to kill many pathogens. Plant in the fall with resistant varieties and maintain a clean garden.

E-mail inquiries and suggestions to lazy.gardener@comcast.net