This warm spell we’ve been having is the perfect time to get out and give your fruit trees, berry bushes and roses a dormant spray against overwintering insects and disease organisms. I planned on doing just that today, but decided that it was too windy. With this gusty wind, who knows where all of the spray would land? Perhaps it will be calmer in the morning . . .
I used to think that I would grow my apples, pears and other fruits “organically” by not applying any pesticides at all. Unfortunately, this natural approach is not satisfactory. Small, misshapen, diseased and wormy fruit are not what I’m looking for. Fruit tree pests are out there, and they will attack unprotected fruit.
Like all commercial fruit growers, organic tree fruit producers spray their trees over a dozen times during the growing season. The difference is that they use natural compounds and botanical insecticides instead of conventional synthetic pesticides.
I’ve chosen to use these organic pest controls in my home orchard, too. But I don’t want to be out spraying all the time! I’ve modified the commercial recommendations so that I’m applying 4 or 5 sprays at the most critical times during the dormant season and in the spring. In summer and fall, I only apply pesticides when I notice a problem.
While I’m basing my spray schedule on the needs of my apple and pear trees, I go ahead and give the first dormant spray to all fruit trees, berry bushes and roses while I’m at it. I give the additional sprays to the cherries and plums, too.
Just be sure not to spray any fruit trees when the flowers are open and bees and other insects are pollinizing them. Remember: dead pollinizers = no fruit!
Here’s the schedule:
- Dormant Spray: Horticultural oil can applied any time during the dormant season, but usually in early spring before the buds swell. This will control overwintering pests and disease organisms. I use Bonide brand All Seasons Horticultural Oil Spray. Since I’ve had bad luck with fireblight disease, I’m adding Bonide Copper Dust/Spray this year.
- At Half-inch Green Bud Stage: When the buds begin to swell and there is ½-inch of green showing, I spray with lime sulfur to control diseases. I use Bonide brand Lime Sulfur Concentrate along with the horticultural oil spray.
- At Popcorn Bud Stage: When the flower buds first begin to open and you can just see a bit of color but they are not fully opened, I might spray again with lime sulfur for disease control. I’ll admit that spray number 2 and 3 are sometimes (usually?) combined into just one.
- At Last Petal Fall: Lime-sulfur plus insecticide at this time is critical to control scab, mildews, rots and blotches, leafrollers and other insect pests. There are a number of good fruit tree insecticide choices; I usually use either Bonide brand Captain Jack’s Deadbug Brew or Fruit Nut & Orchard Spray.
- Cover Spray: Spray the lime-sulfur plus insecticide combo again 5 to 7 days later. This is a key spray to eliminate many future insect problems including codling moths – the worm in the apple!
Having laid a good foundation with the above four to five sprays, I feel comfortable recommending additional sprays “as needed”. Check closely on a weekly basis to make sure you can nip any potential problems in the bud.
Note: I recommend Bonide brand products because they are available at many local independent nurseries. Ask a nurseryperson for another recommendation if they don’t carry Bonide brand where you shop, or look in the OSU fruit pest reference for equivalent products.
Other spring fruit tree tasks include pruning and fertilization.
Prune in early March, to establish a good framework. Remove all dead, damaged or diseased branches. Thin out branches from the center of the trees to open them up to sunlight and improve air circulation. This, in turn, prevents certain diseases. See the OSU fruit production guide for pruning tips.
And finally, fertilization. In early spring, around the same time as pruning, I use one of the Espoma brand natural fertilizers at the rate of 3 to 4 pounds per inch trunk diameter. I also mulch in late spring with compost. This adds nutrition, suppresses weeds and helps to conserve moisture.