Over the years, I've come upon some really crazy ways to keep rodents out of gardens. Those burrowing types — such as rabbits, gophers and ground squirrels — can devastate a vegetable garden or fruit tree almost overnight. They feed on the soft roots of plants, severing the link from soil to stem.
One older instructor related a tale from his own childhood, which illustrates how far people would go to protect their "Victory Gardens." This was during the glory days of DDT, when another nasty carcinogenic pesticide, chlordane, was widely available. Farmers figured out that gophers would not tunnel through soil that contained this chemical. The old-time method was to dig a shallow trench along the outside of the garden fence, then pour a line of chlordane down the center of it. Rainfall would carry the chemical deeper into the soil, creating an invisible barrier to rodents.
Thankfully, chlordane is no longer available, but this idea of creating a moatlike barrier is still viable for organic gardeners. It may be a lifesaver for virtually all rural gardeners, since burrowing-rodent damage is so universal. Instead of toxic chemicals, you can install a row of plants that are toxic to gophers. They do not like digging through these root zones any more than they like going through chlordane-treated soil. In fact, this was the way it was done long before the advent of chemical pesticides.
All species of the genus narcissus are toxic. Gophers avoid them like the plague. I tested this in my country garden because newly planted fruit trees in my orchard could be devastated by our enormous gopher population. I bought a huge quantity of really cheap mixed narcissus for naturalizing in the fall, and planted around the new fruit trees. I used a bulb planter to insert bulbs all round the water well at the base of the plants. Come spring, I had tons of extra flowers for cutting from my fruit-tree wells. And gophers never crossed that line.
This demonstrates how well a line of narcissus can protect a garden. Order quantities now and look for bargains because young undersized ones will cost far less while working just as well. Plant them tightly in a row along the outside edge of your garden fence. This is not only beautiful to behold, it's an enormous source of flowers at the start of spring. Use a mixture of different types so you'll have fragrant jonquils and huge King Alfred daffodils along with more ordinary sorts.
Recently I discovered another plant used this way in old-time gardens in the arid West. Castor bean (Ricinus communis) is a native of North Africa and is surprisingly heat- and drought-resistant, so it doesn't demand too much water. Castor is tropical-looking, and some varieties are quite colorful. It is also the source of ricin, one of the deadliest poisons on Earth. It's no wonder they were planted around gardens to keep gophers at bay, but do beware of planting in locations shared by kids and pets.
With bulb-planting season almost here, online bulb sellers will have plenty of stock for naturalizing. At Brecks.com, you can buy 120 mixed narcissus for about $75. Or shop around for the best price from other sources. If you're waging war against these rodents and losing the battle, it's time to plant your moat now for a trouble-free garden next year.
Maureen Gilmer is an author, horticulturist and landscape designer.