Wow! It's 62 Degrees in Central Wisconsin and Indicator Plants Are Indicating What?

Daffodils blooming on May 1.

Skies are blue and the sun is shining! My car thermometer says it was 62 degrees at 3:30 P.M.

Wow! Our first really nice day and I was inside with students who would much rather play video games than learn to keyboard. When I first got home I took a few moment to sit and soak up the sunshine, check out my daffodils, and notice the hepatica was in bloom.

My bloodroot, which goes by fairly quickly, although I have it planted in the shade on the north side of my house is very sensitive to that 50 degree number; shot up its still unfurled leaves. I figure two days of this type of temperatures and it will bloom.

I saw my first dandelions in bloom today. My forsythia is in glorious full bloom. All this leads me to the next thing gardeners need to think about. The calendar for when to do what in the garden is all messed up. For those of you who plant potatoes when the first dandelions bloom, here you go! That forsythia says to plant those peas. For those of you looking for a wood tick, get out your repellents.

And those of you looking for that biofix date where you will see a codling moth in your traps three days in a row and whatnot, you better hang your traps and start thinking about pheromone baits.

Normally, you would spray a dormant oil on fruit trees sometime in March when the temperature was to be above 40 degrees for the next 6 hours. If you have not done that you need to do it ASAP. You want to spray your dormant oil before the buds have green tips and the leaves begin. You also want to allow 10-14 days between your different treatments. I sprayed my fruit trees with dormant oil around the 22nd of March.

With April so incredibly cold and raining or snowing, all the typical dates are way off. According to data taken at the Wisconsin Rapids weather station between 1961 to 1990, the first daffodils bloom around March 26. This year, I think it was April 29.

So here goes a short list of indicator plants on what to do when here in the garden in central Wisconsin based on temperature tracking at the Wisconsin Rapids weather station and the resources compiled by the UW-Cooperative Extension.

When violets open apply crabgrass preventer.

When forsythia are in full bloom, tent caterpillars and pine sawflies are hatching.

When common lilacs are first in flower, the first generation of codling moths emerge to lay their eggs. This is the time for pheromone disruptors. About three days after the first lilac begins to bloom, if you are going with your typical spray programs then would be the time. If you are hanging Tanglefoot-treated red balls, have them up before the lilac blooms. Keep the sticky ball about 5 feet from the ground and be sure to re-coat before July 1 to catch any early apple maggots. (Just a note for those of you fearing catching beneficial insects, I used these with Tanglefoot one year and did not catch a single bee of any sort nor any beneficial insects.) Recommendations are for one trap per 50 -100 fruit. On my heavily laden 'Honeycrisp this would be about 4 traps!)

In addition to traps, pheronome disruptors, using landscape fabric to prevent access to soil, be sure to clean up and bag any windfall apples as soon as they fall and pick off any apples showing frass (the jelly like goo that indicates and insect's larva is working that apple).

If you are using traditional fruit tree sprays for coddling moth control, for example malathion, spray at 75% of petal fall, again at 7-10 days after petal fall, and then on a cycle every 10-14 day thereafter.

At this time, the first onion maggots lay their eggs. An organic gardener shared this tip. Interplant onions and carrots by rows, a row of carrots, a row of onions. Carrot fly doesn't like onions and onion maggots are confused by carrots. These two make great planting partners.

So by the time lilacs are in full bloom, those coddling moths are laying their first hatch of eggs on your apple trees. When this group of eggs hatch they will pupate in the ground. If you have laid down black landscape fabric around your fruit trees you will cut down on a large part of this population getting to and out of the soil.

Also around the time the lilac is in full bloom the cabbage maggots first generation of eggs hatch. You might want to think about row covers for your cabbage family of crops. This would make it much more difficult for those yellow and white "butterflies" (I'm told they are really moths.) to lay eggs on your cabbage plants.

Traditional spraying methods for codling moths are spaced about every two weeks throughout the growing season. There have been studies showing two or three properly time application of dormant oil will do the trick versus having to follow a nearly religious twice a month traditional spraying schedule.

If you are attempting to time dormant oil applications on fruit trees, I would time them to the peak moth emergence times, before they have a chance to lay eggs. One application of dormant oil in mid-March (decidedly before green tips), the second application three days after the first lilac blooms, and the third application in typical years about August 3rd (or using indicator plants, a week after the wild bergamot is in full bloom). If you have apple maggot, this third application should take care of those, too.

Some additional correlations for other garden chores:

Plant beets, carrots, cole crops, lettuce,and spinach when lilac is in first leaf. Plant corn when oak leaves are the size of a squirrel's ear. Plant beans, cucumbers and squash seeds when the lilac is in full bloom. Transplant eggplant, melon, and peppers when Irises bloom.