3 benefits of Foliar feeding in your garden and 10 ideas to get you started
“Feeding your plants through the surface of their leaves as opposed to their roots is advantageous for the organic farmer.” - Joanna Pianko
I’ve been gardening for a long time, but only recently have I become infatuated with foliar feeding. I’ve hauled compost, manure and mulch. Brewed liquid fertilizer and watered my plants with compost tea for years. For some reason, I can’t believe I overlooked simple foliar feeding for so many years. Since I began using this method to deliver nutrients to my plants, not only has my garden become more lush than ever, but I’ve drastically cut my need to import fertilizer.
Foliar feeding means feeding your plants through the surface of their leaves as opposed to their roots. Much like humans absorb through our layers of skin, plants can absorb nutrients through the surface of their leaves. This process can be quite advantageous for the organic gardener for many reasons.
Did you know? Plants only produce 15-20% of the sugars that they're actually capable of producing through photosynthesis. Foliar sprays may dramatically increase three-fold, allowing the plant to produce more sugars. This actually puts sugar into the soil microbiome, regenerates soil health, builds up organic matter, and even sequesters carbon! Not to mention, it puts a lot less strain on the soil by not uptaking so many nutrients. This regenerates the living soil microbiome and in the long term, improves plant health and insect and disease resistance.
3 Benefits of Foliar Feeding:
Foliar-fed nutrients are easier for plants to use than root fed. Roots are designed to absorb nutrients, but when plants are forced to rely solely on their roots for nourishment, they are at the mercy of the soil. If the soil pH isn’t just right, if it’s too hot or cold outside, if there isn’t adequate mycelium or organic matter in the soil then roots won’t uptake all the nutrients they need to grow vigorously.
To-Do ✓ Spray organic or home-made fertilizer directly onto the foliage of the plant to bypass all the soil drama and allow your plants to uptake 100% of the nutrients directly to where they need to thrive.
Foliar feeding prevents pests. Pests love your garden plants and will easily attack any plant that grows suboptimally. Plants not receiving adequate nutrition are stressed and aren’t resilient against pests. Foliar feeding adds a boost of nutrition to the plants and cultivates a diverse microbiome on the surface of the leaves that prevents fungal diseases.
To-Do ✓ Foliar feed your plants some probiotics to cultivate a diverse microbiome that prevent fungal diseases and pests in your garden.
Foliar feeding reduces the need for chemicals. No gardener should have to rely on chemical poisons to get a harvest. Completely cut the need for chemical sprays and quit wasting money. Foliar feeding creates stronger, more resistant plants, and the gardener doesn’t need to buy chemicals to protect their plants from pests because the plant is vigorous and capable of defending itself. Pests aren’t as keen on attacking strong plants as they are stressed and struggling plants.
To-Do ✓ Spray diluted yogurt all over your plants’ leaves to prevent and treat stubborn peach leaf curl. Recipes for foliar feeding sprays are below in this article.
How to get started:
Foliar feeding may be done with a spray bottle for seedlings and houseplants. A pressurized sprayer is recommended for the garden. Dilute the solution with lots of water before applying.
The best time to foliar feed is between 7 AM and 10 AM or after 5 PM. This is when the small pores in the leaf bottoms are open. However, if the temperature at 7AM is 80 degrees or above, the spray will be less effective. Spray your plants and trees as often as you like. Some farmers even spray overly-diluted solutions every 48 hours. If you choose to spray more often, then you should ensure your solution is extremely diluted. If you want to spray weekly or bi-weekly then use a more concentrated solution. Make sure never to exceed more than 8oz per gallon of water, and only spray in the early morning or late evening.
What to use:
Foliar spray should contain magnesium, manganese, iron, nitrogen, and phosphorus. Different solutions which can be used in a foliar spray. Here are 10 ideas to get you started:
Kelp is rich in phosphorus
Herbal tea can act as medicine for your plants. Yarrow is one of the best herbs to use because it contains high levels of microbiotics. Use fresh herbs from the garden.
Compost tea and worm tea are rich in nutrients and can be brewed at home (insert link to making compost tea article here)
Fish emulsion. I love using all of Neptune’s harvest’s ocean-based liquid fertilizers diluted in water as a regular bi-weekly foliar spray. It’s very nutritious, loaded with microbiotics, and my plants and trees are noticeably greener and healthier. Beware it’s quite stinky!
Coca-cola! This is a weird one, I know! But Coke (not diet, regular with cane sugar) contains leaf-digestible sugar and phosphorus. Dilute well, use only 4-6 oz cola per gallon of water.
Full fat yogurt. Another weird one, but hear me out! Full fat yogurt is rich in probiotics like lactobacillus and helps fight mold and fungal disease such as peach leaf curl. Use 2-4 oz per gallon of water and spray directly onto the foliage. Spray every 3-4 days for 2-3 weeks to treat peach leaf curl.
Apple cider vinegar is probiotic and prebiotic, enhances microbial populations, and triggers bud development. Spray over fruit trees in June and July when fruit trees set out bud sites for the following year. This is super useful for trees that won’t flower or fruit and works just as well on fruiting vegetables. Try spraying some ACV solution onto tall, leafy tomatoes that still haven’t flowered to encourage fruiting. Use 2-4 oz ACV per gallon water.
Molasses are rich in iron, magnesium and nitrogen. It allows the leaves to intercept more sunlight and encourages better photosynthesis. Sugars are absorbed through the leaves and give the plants energy to grow.
Epsom salts contain magnesium and sulfur and contribute to the development of more chlorophyll. You’ll notice your plants looking greener than ever. Use only a ½ oz per gallon of water for foliar feeding. You can add this to all foliar sprays.
Whey, milk, or powdered milk is a great source of nitrogen and calcium (which prevents blossom-end rot). Amino acid nitrogen is superior to what is usually used in conventional fertilizers, are far more bioavailable and don’t have any of the side effects for your plants. Whereas ammonium nitrate and calcium citrate used in conventional ferts increases susceptibility to pests and disease.
Sources:
Cheng, L. and R. Raba. 2009a. Accumulation of macro- and micronutrients and nitrogen demand-supply relationship of Gala/Malling 26 apple trees grown in sand culture. J. Amer. Soc. Hort. Sci. 134:3-13.
Cheng, L. and R. Raba. 2009b. Nutrient requirements of Gala/M.26 apple trees for high yield and quality. New York Fruit Quarterly 17(4):5-10.
Fallahi, E., I. Chun, G. Neilsen & W. M. Colt. 2001a. Effects of three rootstock on photosynthesis, leaf mineral nutrition, and vegetative growth of BC-2 Fuji apple trees. J. Plant Nutrition. 24:827-834.
Fallahi, E., W. M. Colt, B. Hallahi. 2001b. Optimum ranges of leaf nitrogen for yield, fruit quality and photosynthesis in BC-2 Fuji apple. J. Amer. Pom. Soc. 55:68-75.