This article was written 50 years ago. Some info may be outdated Written by Kenneth Allan in 1976 – Issue #1
Long dismissed as an Old Wives’ Tale or just another exaggerated claim from the radical gardening fringe, the power of marigolds to repel insect and animal pests is very widely talked about today, but, one suspects, not extensively put into
practice.
Part of the problem for would-be users of Marigold Tactics is found in the current seed catalogs, which offer page upon page of marigold varieties with little or no mention of their strength of fragrance. In fact, the situation is compounded by plant breeders who are attempting to eliminate the useful (to us) smelliness of marigolds to make them more publicly acceptable.
As a cautious believer in companion planting, the difficulty I have is that the seed companies do not come out and say, “This is the stinkiest marigold we sell.” While the varieties denoted as African (Tagetes erecta and French (Tagetes patula) are generally regarded to have the oily scent so repulsive to some pests, what is really needed is a list of the common varieties with a smell rating.
In the meantime, William Dam Seeds carry a nameless marigold specifically recommended for the control of root nematodes. A small Canadian company of Dutch extraction (their motto: Daar het ons streven is alleen het allerbeste te leveren), William Dam is dedicated to chemical-free gardening and they assure me this marigold is of the old, tall, smelly variety.
For the skeptics, Dutch nematode specialists have isolated the root exudates of African marigolds and found them to be sulfur-containing substances known as thiophenes. Agricultural researchers in Scotland have showed that a crop of Marigolds would eliminate 55 per cent of potato nematodes in infested fields. The planting of Mexican marigolds (Tagetes minuta) in rows of potatoes have been shown to keep destructive wireworms back for a distance of three feet.
I’m not sure if there is any definite connection between the proved excretion from the roots and the odour of marigold foliage, but I do know that if I’m going to plant marigolds to kill nematodes and wireworms, I might as well plant strong smelling varieties that have a reputation for discouraging aphids and rabbits as well.
William Dam recommends the planting of marigolds near cabbage to ward off cabbage butterflies. Other crops said to be protected by them are: cauliflower, radishes, kohlrabi, Brussels sprouts, turnips and strawberries. I am adding tansy this year, because all companion planters recommend it, and wormwood because will have a country garden for the first time and have heard that wormwood repels many small animals (as well as flea beetles and the cabbageworn butterfly).
Both plants are hardy perennials and should be planned as more or less permanent border crops. The tansy (Tanacetum vulgare) grows to a height of three to five feet, with button yellow flowers and leaves famous for their medicinal uses in teas and tonics.
Tansy is planted in spring and is easily grown from seed or from rootstock obtained from an established colony. It spreads rapidly and therefore probably has no place in the smaller garden. For the gardener with more space, however, it can be kept in defined borders and has a reputation for keeping away ants and various flying insects, including moths, Japanese beetles and squash bugs.
Wormwood (Artemisia absinthium) grows wild in Britain, where it is much valued as background plant with pleasing gray or silvery-grey foilage. The essence of wormwood formed the base of absinthe liquor and is often mentioned in the lore of folk medicine. It is said to repel mice and its dried leaves can be brought into the house to work against moths and fleas. Wormwood seeds are small and should not be planted deeply. They can be started now indoors or in a seedbed, and trans-
planted when several inches high. The plants grow best in sunny areas or spots with only light shade, and reach two to four feet in height.
Garlic is the only garden vegetable that has no insect enemies, and IS a favorite for interplanting throughout the garden. It is recommended for repelling everything from aphids to peach borers, and it can be ground up and used as an antibacterial spray. The effectiveness of plants like these is very difficult to evaluate. If certain insects stay out of your garden, maybe you were just lucky. If some do show up, maybe it would have been much worse.
I have been using these plants for several years and have each year had lots of bugs in the garden, but never enough to cause crop failure. There were also lots of ladybugs and toads. If the bugs were to move out completely, the ladybugs and toads would have to leave too, making the area much more susceptible to an epidemic.
To observe all the suggestions of companion planting would require more arranging than I care to do in my garden, but there is one bit of planning than is fairly easy and seems worthwhile. Beans and potatoes go in alternate rows because beans repel the Colorado potato beetle, while potatoes drive of the Mexican bean beetle. Sunflowers go to another part of the garden because they are said to get along poorly with the potatoes.
Companion planting wil not keep all the bugs out of your garden, but that is not necessary for the sake of the vegetables however urgent it may seem to the overly fastidious gardener. Most plants produce more greenery than they know what to do with, so a few perforated leaves won’t hurt (though you should pick of the tomato hornworm, which can strip a whole plant given a few days).
Using all or a few of these preventative measures can be cheaper and easier than spraying with chemical insecticides. Prettier and more virtuous, too.
Sources *** Originally published 50 years ago in 1976. Some info WILL be out of date – FOR COMPARISON OF 50 YEARS
William Dam Seeds, West Flamboro, Ontario:
Smelly Marigolds (Tagetes): $1.50 per ounce; $3.50 for 1/4 pound.
Tansy (Tanacetum vulgare): 50¢ per packet; $1.25 for ‘/16 ounce.
Wormwood (Artemisia absinthium): 50¢ per packet; $1.25 for ‘/s ounce.
Garlic Sets (Allium sativum): 75¢ per 1/4 pound; $1.40 per 1/2 pound.
(Note: Handling charge of 45¢ on all orders under $8.00 and $1.00 extra for all orders sent to the U.S.)
The Redwood City Seed Company. P.O. Box 361
Redwood City, California 94064
Tansy: 30¢ per packet; $1.25 for / ounce.
Wormwood: 25¢ per packet; 75¢ per ounce.
Mexican Marigolds (Tagetes minuta): 50¢ per packet (grow to six feet).
French Marigolds (Tagetes patula): 50¢ per packet (either yellow or brown gold mix (specify); grow to about one foot).
(Note: Redwood City charges 25¢ for their small, but fascinating, catalog. For seeds shipped either to Canada or within the U.S., they charge the following for handling and postage: Two cents per packet, with a 25e minimum order. Ten cents for each ounce of seed ordered.)
Originally published 50 years ago in 1976. Some info may be out of date.
