Messenger, marketed by Eden Bioscience, was accidentally discovered in 1992 by researchers at Cornell University who were studying fire blight in pears and apples. The harpin protein, they noticed, caused plants to activate their defenses. Tricked into thinking they were being attacked, the plants immediately began triggering their immune systems.

"It's kind of like a flu shot for your plants," explained Lisa Bedbarski, Eden Bioscience home and garden specialist. "When the plant recognizes the protein, it increases photosynthesis, vigor and flower production."

Because the plant doesn't realize that it really isn't under attack, it takes in more nutrients and beefs up its defense mechanism, preparing itself for an assault that never comes.

"Reminds me of Chicken Little running around telling everyone the sky is falling, though it really isn't," Michelle Semerad wrote in a 2005 issue of the Alaska Master Gardener Association's newsletter.

Because, you see, Messenger is a bit of an ambiguity. While the product is endorsed by the National Gardening Association, the American Rose Society and the National Home Gardening Club, gardeners around Anchorage can't seem to agree on its merits. Some love it, some hate it and others are still trying to make up their minds. While there has been little hint of Messenger harming plants, there are those who claim it didn't help them much either.

Those who experienced unsatisfactory results wonder if the weather had anything to do with it or if they were using the wrong dosage. Successful gardening, after all, relies on so many variables that it's difficult to pinpoint why one plant thrives and the one next to it dies.

Steph Daniels, assistant nursery manager at Bell's Nursery & Gifts, noticed marked improvements after using Messenger, especially on an ill fuchsia tree.

"Last year we had a big aphid problem," she said. "And while it doesn't do anything about insects or prevent insect attack, it can help the plant survive the onslaught."

Bill Borchardt, owner of Arthur Campbell Nursery in Anchorage, agreed. He started using Messenger last year and ended up with healthier, more resistant trees and shrubs.

"Oh yeah, we could really tell the difference," he said. "If you take two plants, spray one with Messenger and not the other, you'll know right away which one got the goods."

"It's definitely made my plants larger and stronger," she said. "Their immune systems are healthier, and I've had much less bug and fungal problems."

Dea Calvin, owner of Forget Me Not Nursery, was less enthusiastic. He tried Messenger a couple of years ago and didn't notice much result.

"I was kind of indifferent," he said. "We used it on a variety of containers and hanging baskets, and I really couldn't see any difference in the ones we used it in the ones we didn't. Maybe we weren't using the right application, or maybe the plants were doing well and didn't need anything else."

Ruth Ann Dickie wasn't terribly impressed with Messenger either. She used it last year and didn't notice much change, though a friend "went bananas over it." Dickie, who believes the key to gardening success is in the feeding, has decided to give Messenger another try.

"Last year we had kind of a goofy summer," she said. "So I thought, 'Maybe I need to be more attentive. Maybe I need to watch the plants more to really see what they're doing.' I used it on my seedlings. Now I just have to wait and see."

Master gardener Dana Klinkhart tried Messenger last summer and found that her plants were less prone to pest and fungus attacks.

"I had a climbing rose that always gets aphids, and last year it didn't," she said.

This year, she performed her own experiment with sweet pea seedlings, using The Puffer, a new Messenger seed treatment, on half of the seedlings and nothing on the rest.

"The story is that the ones that did have Messenger were slower to sprout and the least hardy."

Klinkhart added that her experiment wasn't scientific and that the seeds might have bee
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