Organic Home Orchard Spraying Tips
Renowned organic tree fruit grower and author Michael Phillips recommends a “holistic” spray regimen (now sold as our Holistic Orchard Spray Kit) to help prevent disease and enhance both tree & fruit growth.
For a detailed discussion of these ingredients and how they work together to serve your fruit trees, see Michael Phillips’ book The Holistic Orchard.
Note on Organic Molasses: Organic molasses tends to have some type of pH buffer in it, which sometimes prevents the fermentation process. You can add in an equal amount of vinegar (apple cider, wine, etc.) to the molasses to help break the pH buffer.
MICHAEL PHILLIPS’ HOLISTIC SPRAY RECIPE
- Fish Hydrolysate: Feeds soil and arboreal food web.
- Neem Oil: Contains Azadirachtin compounds that deter pests and disrupt their life cycles. Neem also is said to stimulate the tree’s immune system, give nutrients to foliage and feed the arboreal food web. Caution: pears are quite sensitive to neem oil, especially after bloom, so spray them lightly, or cut the neem rate in half if you’re spraying lots of pears.
- Liquid Kelp: Promotes growth and helps trees adapt to stress.
- EM-1: A probiotic inoculant that colonizes the branches and fruit with beneficial microbes to promote fruit growth and disease resistance.
You can increase the volume of effective microbes provided by EM-1 through fermentation. Assuming you spray ~10 gallons of the Holistic Spray Recipe per spray day, and you spray EM-1 five times in the spring and once in the fall, you’ll need to brew 5 quarts of activated EM-1 for the spring, and 1 quart for the fall (don’t brew all 6 quarts at once, as the brew lasts only 45-60 days).
Recipe for 5 quarts of activated EM-1: Mix 1 cup EM-1 and 1 cup molasses with 4½ quarts warm water (110°). Put into airtight bottle(s) or brewing container with an airlock. Ferment at room temperature for 3-5 days. If you use an airtight bottle, unscrew the lid daily to release pressure buildup. After 3 days check the pH (using our pH strips). Once the pH has dropped below 3.8, the fermentation is done. Let the activated EM-1 rest for 5-7 days, then it is ready for use. The completed product should smell slightly of alcohol.
For 1 quart of activated EM-1: Mix 1½ fl oz EM-1 and 1½ fl oz molasses with 3½ cups warm water (110°). Follow same steps as above.
Makes a 4-gallon ready-to-spray batch. Mix in a 5-gallon bucket in this order:
SUGGESTED SPRAY PROGRAM
- ⅓ cup Neem Oil—warm up to liquefy.
- 1 teaspoon biodegradable dish soap—stir to emulsify neem.
- 1 quart warm water
- ½ cup molasses (then stir again)
- 1¼ cups Fish Hydrolysate
- ⅓ cup Liquid Kelp
- 1¼ cups activated EM-1 (see recipe above)
- Add water until you reach the 4 gallon mark, then stir one last time.
Coat trees—including the trunks—to the point of runoff, about 1½ gallons per mature fruit tree. We recommend using the Solo Deluxe 4-Gallon Sprayer. Treat this suggested schedule as a starting point; every site is different and requires a custom program. For example, trees with cedar apple rust or brown rot issues may require additional spraying for effective management.
- When green leaf tips emerge: Fish, Neem, EM-1 and Kelp. Fish and Neem rates can be doubled for this first spray, except if using on pears.
- When buds turn pink: Fish, Neem, EM-1 and Kelp.
- When blossoms open (optional): ONLY EM-1 and Kelp. To help prevent apple scab and fire blight, increase Brix, and attract pollinators.
- When petals fall: Fish, Neem, EM-1 and Kelp.
- 7-10 days after petals fall: Fish, Neem, EM-1 and Kelp.
- Post-harvest, after about half the leaves have fallen: Fish, Neem and EM-1. Spray trees as usual, but also aim at the ground to hasten leaf decomposition.
Other Organic products that can help manage some of the worst fruit pests in New England [manufacturer’s recommended usage rates per gallon of water shown in brackets]:
|Surround WP (kaolin clay) [½#/gallon].
||Primarily for Plum Curculio, but acts as a secondary defense against other pests. “Do as you oughter: add Surround to water.” Allow to sink entirely before stirring. Spray solution immediately, do not store in sprayer or it will clog. While spraying, agitate frequently to keep clay in solution.
|Monterey Garden Spray (0.5% Spinosad) [1-2 fl oz/gallon].
||Primarily for European Apple Sawfly and Apple Maggot Fly; will also kill Lepidoptera, but better to use Bt if targeting exclusively Lepidoptera. Toxic to bees; spray while bees are not foraging—right at sunrise or right before sunset!
|Safer Caterpillar Killer (Bacillus thuringiensis, or Bt) [1-4 teaspoons/gallon].
||OR Dipel DF for larger Bt applications [¼ lb/25 gallons].
Primarily for Codling Moth and Obliquebanded Leafrollers. Add 1½ teaspoons molasses per gallon to act as a feeding attractant. Bt degrades fast (in 3-4 days), requiring more repeat applications.
|MilStop (potassium bicarbonate) [1-2 Tablespoons/gallon].
||Primarily for Sooty Blotch and Flyspeck. Do not expose to moisture/humidity in storage—it will turn rock-hard!
|Safer Garden Fungicide (12% micronized elemental sulfur) [1-2 fl oz/gallon].
||In the context of Holistic Orchard Management, the goal is to use sulfur minimally and only as a last resort. It can be used to help inhibit Brown Rot of plums right before harvest; sulfur will also kill Powdery Mildew and Apple Scab spores. For managing Apple Scab, some growers prefer to use the Holistic Orchard Spray as a preventive measure, which greatly reduces the need to spray sulfur or other concentrated fungicides. WARNING: Do not spray sulfur when temperature exceeds 80°, otherwise foliage could burn!
|ThermX 70 (sticker-spreader, 70% yucca solids) [½ teaspoon/gallon].
||Most useful for helping Bt adhere, but can be used with any of the above products. Add last to any tank mix because it foams a lot.
HELPFUL RESOURCES FOR TREE-FRUIT GROWERS
- Holistic Orchard Network (Michael Phillips); click here for his recommended seasonal checklist.
- University of Maine
- Cornell University
- University of Vermont