Keeping Your Trees Healthy with Holistic Spray
Each month, we share expert-led training sessions to help community orchard stewards grow and care for thriving fruit trees. On this page, you’ll find a recorded workshop, a summary of key takeaways, and additional resources to deepen your knowledge. Be sure to explore past workshops for even more insights into urban orcharding best practices!
Interested in attending a workshop? Sign up for our workshop series email list!
Workshop Summary:
Overall Spraying Guidelines
Traditionally, the view of a spray is used to kill pests and diseases. Often, with harsh and toxic chemicals that cause harm to the environment and the people who apply them.
With this solution, our focus is to jump-start a healthy growing season by providing the tree with everything that it needs to produce abundant crops of healthy, nutritious fruit.
Just as the tree is waking up from dormancy in the spring, we coat the surface of the leaves and bark crevices to ensure it has all it needs to grow.
This is not a solution just to kill pests and disease: our goal here is to support the health of the tree overall.
By applying this solution to the leaves, we’re making sure all of the nutrients are available for the tree to grow healthy fruit each season.
The Holistic Orchard
Source material is The Holistic Orchard” Book by Michael Phillips, Organic Orchardist reference “go to” pg 143 shows spraying
What is Holistic? “The treatment of the whole person, rather than just the symptoms of an illness.”
Our actions are beneficial and feed into improving soil and tree ecology over time; “microbial world”
Comparison of the tree’s immune system to the human immune system
Holistic vs. Allopathic Approach
Holistic= Treats the individual | Allopathic= Treats the disease
Foliar Feeding & Stomata
The fastest way for trees to absorb nutrients is through their leaves, in a fine mist, rather than through the soil. The process that we are using to feed the trees in this case is called Foliar Feeding, foliar being a reference to the leaves of the tree.
On the underside of the leaves are small openings - called the stomata - which allow nutrients to pass through the surface of the leaf into the tree’s system.
Liebig’s Law of the Minimum
Principle in agriculture that states: that the growth of an organism is limited by the most scarce resource. It's a fundamental principle in agriculture and is used to model biological growth.
No matter how much you give of all resources, growth will be limited by whatever the tree is missing. This shows the importance of trace minerals in small amounts for overall tree health
For example, boron plays a key role in this process of flowering and seed and fruit formation. Without an adequate amount of available boron during this process, the tree won’t be able to complete these processes, and leave extra sugars in the leaves that attract sugar-feeding insects, like aphids.
Purpose of Ingredients in the Spray
Neem Oil
Seeds of the Azadirachta indica tree from India, this raw seed oil supplies essential amino acids, vitamin E, and omega-3 Fatty Acids, which benefit the tree deal with stress insect control
Azadirachtin in the neem smothers over-wintering insects and eggs; neem is toxic to pollinators when wet, don’t spray in bloom or during daytime hours
It’s important to note: Not all neem is processed the same and the end results can vary widely. Make sure that the brand you are using has the words “Cold PRESSED” on the label.
“Candlewax” consistency: note that neem oil at cold temperatures below 60 will be solid if not warm. Soak the bottle in warm water to liquify again.
Liquid Fish
This is produced through composting the remnants of fish-processing facilities. Not the same as fish emulsion.
It provides nutrients for the microbes living on the leaves and bark. The nitrogen supports healthy growth, the omega-3 fatty acids support fruit development and the ability to deal with stress growth, cell walls, as well as food for the beneficial microbial population living on the surface of the leaves.
Spraying these nutrients on the flower buds just as they begin to open in the spring, provides better fertility for the flowers and thus a better fruit set
Effective Microbes
Beneficial microbial growth coats the surface of the leaf and bark; promotes beneficial bacteria and fungi on the leaf surface to compete with pathogens; diseases that occur on the leaves of the trees “Induce systemic resistance action within the tree itself” (pg 188); “foliar disease can be significantly reduced when the leaf surface is occupied”
“Creating Balance” of pathogenic compounds and beneficial microbes; we are acting as stewards of the microbial environment living on the surface of the leaf. Again, just like our human immune system, you could compare this to taking a probiotic. The presence of these beneficial bacteria helps to ensure a healthy, happy tree that can take on all the challenges of the environment.
You can make more of your own by adding water (mix ¾ cup of probiotic formula per gallon of water and ¾ cup of molasses to “activate” it in a sterilized jar; let ferment in a warm room for 7-10 days. When completed and ready for use, it should have a sweet, earthy smell).
Seaweed/Kelp Meal
Kelp meal, a powdered seaweed product, provides a broad spectrum of minerals (like boron, copper, iron, zinc, cobalt, manganese, and selenium) that are readily available for the tree to absorb.
As well as growth hormones called cytokinins, growth hormones that manage growth, stimulate cell division, promote healthier root systems, and make the tree better thus a better resistance to pathogens.
Natural Soap
The soap blends (emulsifies) the neem oil and water and allows for more complete coverage of the ingredients of the spray
Isn’t all soap natural? Not necessarily! Natural soap is made from all-natural ingredients, whereas some soaps are petroleum-based and have synthetic ingredients and added preservatives. Make sure it is not ANTI-MICROBIAL.
Credit: Michael Phillips
Spray Equipment
The size of spraying equipment you will need depends on the size of your orchard. Our general recommendation for backpack sprayer size is:
1 Gal. Sprayer: 5 Trees (1-3 yrs old); 2 trees 3yrs+
2 Gal. Sprayer: 10 Trees (1-3yrs old); 5 trees (3yrs+)
4 Gal. Sprayer: 20 Trees (1-3yrs); 10 trees (3yrs+)
Sprayers can clog, especially with neem on cold days, so be sure to use filters included in the sprayers with each use
Make sure to flush out with clean water after each use to prevent build-up lean out. Once empty, fill the sprayer with clean water until it sprays clear
As a backup, have a 1 or 2-gallon pump sprayer just in case your primary spraying device has an issue
When to Spray Trees
Spraying starts will depend on the stage of the dormancy (see photos below)
Dates will change every year depending on winter/spring temperatures (i.e. March/April/May)
Best to spray during the dusk/dawn hours with no rain in the 48-hour forecast; ideal temperatures above 60
DO NOT Spray when blossoms are open, neem oil is toxic to pollinators when wet
5 Core Sprays
1st Spray = ¼ inch green
2nd Spray = Pink Stage
3rd Spray = Petal Fall
4th Spray = After Petal Fall
5th Spray = 40% Leaf Drop
Spray Recipe
(1st & 5th Spray)
(2nd - 4th spray)
Overall Spraying Takeaways:
Holistic Spraying requires a lot of timing for different species, but you will see results! Works on vegetables as well, especially fungal prone like tomatoes!
Most important spray is 1st and 4th! Targets insects and disease emergence
Order of Spraying by Tree Family (Target Earliest Blossoms First):
Apricots, Plums, Peaches, Asian Pears, Pears, Apples
Cultivar selection is important for less spraying requirements; Apples & Peaches are more difficult than Paw Paws & Figs
Keep track of your spraying dates in notes or calendar
Don’t spray during blossom, spray at dusk/dawn hours (neem during sunlight will burn leaves) ideally no rain in the forecast
Spray to cover the entire tree, to the point of “run-off” (drops of spray start accumulating)
Adding nutrients via leaves will improve the nutrient quality of fruit
Use the core recipe and adjust it to your orchard & growing region, there a lots of ingredients you can customize your spray and make your own amendments
(Next workshops!)
Additional Possible Spray Ingredients
(To be discussed at June Workshop)
Microbial Support / Anti-Fungal:
Worm Castings / Compost Tea
Unsulphured Blackstrap Molasses
Lactic Acid (KNF) / Whey
Raw Apple Cider Vinegar
Cueva / Copper Fungicide *** (Allopathic / Don’t Mix with holistic spray)
Nutrients / Minerals:
Plant Teas (Nettles, Comfrey, Horsetail, Dandelion: KNF)
Sea - 90 (Evaporated sea water)
Rock Dust / Azomite (Minerals)
Calcium Extract (Eggshells, Sea shells: KNF)
Insect Protectant:
Kaolin Clay (Surround WP)
Bt
Spinosad
Garlic Extract
Fire Blight:
Agriphage
Regalia
Blossom Protect (Beneficial Yeast)
Double Nickel
