- Author: Elvira Bautista DeLeon
I have been a sucker for garden myths. There are so many YouTube videos on the benefits of making liquid tea fertilizer from comfrey leaves for garden plants and vegetables; eggshells are good to include in a compost pile and they provide calcium for better fruiting; pinching suckers off tomato plants promote better growth; etc., etc. I have three comfrey plants growing in the ground and when they grow bigger, I plan on following the YouTube recipe for making comfrey liquid fertilizer. I have used oven-dried eggshells which I ground into powder and mix with water for watering tomato plants, and I snapped tomato suckers last planting season.
Many garden myths began a long-time ago and have been passed down from generation to generation. Each person believes what has been told them by a gardening peer or mentor and they then pass the information along to other people who show interest in gardening or are new gardeners (I am one of those persons). When I was growing up in the Philippines, for example, I saw barrio farmers set small fires from yard waste to smoke their mango trees. I was told it protected the trees from pests prior to fruiting. I still have no idea if tree-smoking helps.
I have just finished reading the Garden Myths Book 1 written by Robert Pavlis, an educator, and a Master Gardener with over 40 years of gardening experience. He is the owner and head gardener of Aspen Grove Gardens, a six-acre private botanical garden in Western Ontario where he grows more than 2,500 varieties of plants. I visited his garden on-line, and it is truly magnificent. Mr. Pavlis is a chemist and a biochemist who enjoys “the truth about things like plants, animals and nature.” He writes articles for magazines and websites and publishes gardening blogs.
In his book, Robert Pavlis lists 121 garden myths on houseplants, gardening practices, soil, fertilizer, composting, mulching, vegetables, care of specific plants, trees and shrubs, houseplants, insect pests, animal pests, diseases, winter protection, and ponds.
Let's see what Robert Pavlis says about some of my gardening practices.
Myth #23: Comfrey is a great dynamic accumulator.
Dynamic accumulators are plants that accumulate higher levels of nutrients in their plants and roots.
According to the author, comfrey, which is very popular among Permaculturists and organic gardeners is NOT a dynamic accumulator.
Comfrey does not have high levels of any nutrient other than it can be a good source of organic matter, but it is not a super source of nutrients. He said comfrey is no better than other common nutrient sources such as alfalfa, crimson clover, cottonseed meal, annual rye and soybean meal. He said science does not support the use of dynamic accumulators and he does not see the attraction for growing comfrey.
Myth #49: Eggshells are good for the compost pile.
Adding eggshells to the compost pile is mostly a myth. According to the author, while chicken eggshells contain a variety of nutrients that plants can use including 50 ppm calcium, 39 ppm sulfur, 12 ppm magnesium, 12ppm potassium, 21 ppm sodium and 5% organic matter (the inner white skin), you will need a lot of eggs to add any significant amount. Also, eggshells do not decompose in slightly acidic or alkaline soils even when pulverized into powder; they take many years to add value to the garden. Although the powder disappears and cannot be seen, they have not chemically decomposed. Even in acidic soil, eggshells decompose in a very slow process. Finally, the author states that in most situations, eggshells add no value to the garden. The exception might be finely ground eggshells (60 mesh) added to acidic soil. They don't harm the garden, so he says if it makes you feel good, go ahead and add them to the compost pile.
Myth #59: Suckers must be removed from tomato plants.
A sucker is a rapidly growing, upright secondary vegetative shoot that develops from the root, crown, or stem of a plant (CA MG Handbook definition).
According to the author, suckers do not need to be removed (suckers are the side branches that grow at the point leaves join the main stem). A tomato plant will grow and produce well if you leave all the suckers on the plant, BUT there some reasons you might want to remove some or all of them.
Pavlis provided the following table to compare different techniques for growing tomatoes:
Pavlis lists the following best practices regarding suckering of tomato plants:
- Remove suckers by hand, with a quick snap, before they are three inches long. Prune on a sunny, dry day so the wound dries quickly.
- Pruning suckers will result in larger fruit which, for the homeowner, maybe more meaningful than overall productivity.
- The cage method, with some suckering later in the season, works well for many growers.
- The issue of suckering is less important than selecting the right variety and watering properly.
- Do not remove suckers on determinate tomatoes.
What is my take-aways from reading the Garden Myths? Garden myths will always be around until science debunks and proves them otherwise. Gardening knowledge is important if you want to move past being a hobby gardener. Do not believe everything you watch on YouTube gardening videos until they can be backed by science. Grow your knowledge base by having a personal relationship with your garden.
I am grateful I have started my journey as a Master Gardener. I will continue to listen to MGs who have more years of experience than me in the field of gardening while at the same time doing my due diligence in finding research-based options to inform my choices on different gardening techniques and practices.
I give Robert Pavlis' book a thumbs up! Easy to read with tons of good science-backed information. He has a good sense of humor, too.
Some Excerpts from Garden Myths Book 1, Robert Pavlis, First Edition 2017.
CA Master Gardeners Handbook, Second Edition. Dennis R. Pittenger, Editor. UCANR Publication 3382. Reprint, May 2017.