Master Gardeners: Garden Myths – are they fact or fiction?

Published 12:08 am Saturday, July 17, 2021

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By Sheri Bethard

Orange County Master Gardeners Association

Garden Myths – are they fact or fiction? Let’s look at 10 of them and see what the research says.

Myth 1 – Compost piles smell awful

FACT: If your compost pile has anything but a pleasant earthy smell, it’s not being properly worked. Anaerobic composting means there might be a lack of oxygen in the pile. It will break down slowly but still have a swampy odor. You must turn the pile regularly to introduce oxygen and help mitigate any odor. Adding dry leaves and some soil will help keep the materials from turning slimy. Remember DO NOT ADD any meat products.

Myth 2 – To ripen green tomatoes, set them on a sunny windowsill

FACT: Sunlight is not needed to ripen tomatoes. For slow ripening, wrap in newspaper individually to contain the ethylene gas given off by other fruit therefore hasten ripening. Place in a cool place such as a pantry or closet. You can store ripe and unripe fruit together.

Myth 3 – You can’t grow anything near a black walnut tree

FACT: Black Walnut trees release an allelopathic chemical called juglone, which inhibits the growth of some plants, many others can grow beneath or near them such as Zinnia, daylilies, phlox, Shasta daisy, begonias, and purple coneflower to name a few.

Myth 4 – Newspaper and cardboard are superb weed barriers

FACT: These materials can be used as weed barriers and covered with mulch. The problem is they could impede water penetration and gas exchange if they become too wet or even too dry. The same goes if they are applied too heavily. Use no more than 4 sheets of newspaper or one layer of cardboard before mulching.

Myth 5 – Paint tree wounds after pruning

FACT: This is an old practice of tree care which has fallen out of favor. In most cases, painting a wound doesn’t serve a purpose and could negatively affect the tree. One exception is if you are pruning a tree that could be threatened by disease-carrying beetles attracted to a fresh wound, then paint it. Some oaks should be painted as they are susceptible to oak wilt.

Myth 6 – For the best garden soil, cultivate regularly

FACT: Some cultivation is good for heavy or compacted soil but too much can turn the topsoil into a powdery dust, thus repelling water and is not conducive to root growth. Frequent tilling can dry the soil out as it is exposed to the sun and cut down on the number of beneficial microbes it contains. Remember the great dust bowls back in the early 20th century you read about in history class? They were from too much cultivation and not rotating crops.

Myth 7 – Pepper plants aren’t setting fruit because of rich soil

FACT: Overly rich soil will favor foliage over flowers, it won’t stop plants from bearing fruit. The lack of flowering could be due to the weather. Most plants, have flower drop if the temperatures are below 55 degrees F or higher than 85 degrees F. Many pepper plants are temperature sensitive.

Myth 8 – Wood chips make the best mulch

FACT: This depends on where you are using them. They make a wonderful mulch for a natural garden but hold too much moisture for cacti and succulents. Don’t spread more than 3 inches thick and don’t pile against plant stems as this can cause problems with disease and bugs.

Myth 9 – Water plants daily

FACT: Container plants may need watering daily but those in the landscape do not. Water them 1-2 times per week and water deeply. Shallow watering encourages roots to stay close to the surface, thus the plants could require more frequent watering. You want roots to go deep so they are self-sufficient during dryer periods.

Myth 10 – Leaving grass clippings on lawn will cause thatch to build up

FACT: Short grass clippings do not contribute to thatch – a thick layer of dead plant debris that makes it difficult for new turf to emerge. It is best to leave the clippings in place and not bag them especially if you have a mulching mower. It is a free source of nitrogen for your lawn. Always keep your mower blades sharp.


For more horticultural information please check our website and if you have any questions, please call our Hot Line at 409 882-7010 Tuesday and Thursdays from 10 a.m. – 2 p.m. or email


We will be starting our next Master Gardener class Thursday August 26 at 6 p.m. Classes will run until 8-8:30 p.m. each Thursday thru December 9 at the Orange County EXPO Center on FM 1442. There will be some Saturday classes and field trips. The fee for the class will be $150 which includes your training handbook, supplies and speakers’ fees. For more information, please email or check our website above.