I grow 5 acres of several varieties of pumpkins, squash and gourds. In 1998 and 1999 as plants were emerging I had to spray every day for cucumber beetles. After learning about seed treatment with systemic insecticides in 2 studies I bought some Admire (16 oz. Liquid was $88 US). Admire has 21.4% Imidacloprid as the active ingredient. There are several products with this active ingredient. The 2 studies and the products spec sheet did not provide any useful details on how to treat the seeds.
I decided to mix 2 teaspoons of Admire with 16 ounces of water. Seeds were soaked for a minimum of 10 minutes just before planting. There was not any noticeable affect on germination.
This treatment was effective for up to 10 days after plants emerged. After 5 days there were 50 to 75 dead cuc bugs under many plants. After 10 days a lot of the bugs under plants were still crawling and there was some evidence of chewing on the underside of leaves. At that point plants were sprayed with 1 tablespoon of Admire in 1 gallon of water, which was effective for about 10 more days. At that point many bugs under plants were crawling. In future studies it would be valuable information if it could be determined if these crawling bugs are laying eggs.
I continued to use Admire every 7 to 10 days on my Atlantic Giant plants and on 7 Burpee Prizewinner plants. It controlled cucumber beetles, squash vine borers, aphids and newly hatched squash bugs. It is uncertain if it had any significant affect on adult squash bugs.
In early October my Atlantic Giant plants looked the best that I remember. In prior years I did a good job of keeping "borers" out of vines but a lot of leaves would collapse because of borers in the stems. This year I did not see a leaf that collapsed due to borers. By mid-August aphids were always present and by mid-September many leaves on the outer edge of plants were dead from hundreds of aphids on the underside. This year I couldnít find an aphid under leaves. I had always done some spraying for aphids, but with my equipment I could not control them.
The Admire spec sheet said it was very toxic to bees. At sunrise after hand pollinating (and covering) female flowers I attempted to remove and destroy all unwanted female and male flowers. On the 7 Burpee plants I did not consistently find every male flower. The next morning I would find 2 to 5 bees (some still alive) in these flowers. Several times I placed crawling bees on a piece of plywood. They always died.
Future use: In 2001 I will soak most of my seeds for a minimum of 10 minutes using 2 teaspoons Admire in 16 ounces of water. I will experiment using 2 teaspoons in 8 ounces of water in a small area. Also I plan to compare soaking seeds for 30 minutes with 10 minutes. Since I donít know if the crawling bugs (at 10 days) are laying eggs I will spray with Admire 7 to 8 days after plants emerge, and again in 7 to 10 days. After that I will use non-systemic insecticides on everything except my giant pumpkins and squash.