Raised bed and path woes

Q: We are starting our first garden of raised beds in Seeley Lake. How much do we have to worry about soil contaminants in our garden beds? Is there some way to keep the soil in good health from year to year?

A: It has been said that if a gardener takes care of the soil, the rest of the garden will take care of itself. The soil is where everything starts. The dirt is full of living organisms--billions of them in every teaspoonful. Yes, that is right. There are billions of fungal spores, bacteria and a variety of other microscopic creatures in every teaspoon of garden soil. They form the web of life which nourishes our food, our flowers and us.

With soil being a living mixture of so many things, it is really hard to have it contaminated, since the soil is always busy healing itself. If dirt has been filled with industrial pollutants or if it has been buried under city pavements, it will need time for restoration. Otherwise any source of soil will be healthy.

It may not be full of nutrients, though. Since the soil in raised garden beds is going to work hard, it is well to start with rich food for vegetables. Local topsoil may or may not be rich. Forest soils are notoriously short on food supplies.

The soil in raised beds also needs to be full of air spaces. It needs to drain water freely but also hold moisture. Those qualities require a big percentage of decayed organic stuff--compost and manure, usually. If raised beds are filled with three quarters soil and one quarter compost, all the plant roots in the beds should be well fed. Nor do the components need to be mixed thoroughly. Worms and other creatures in the soil will take care of the mixing.

Because a lot of soil nutrients will become part of the vegetables, the gardener should remember to replace them. An inch or so of organic additives once a year will take care of that. The additives can be compost, manure or dead plants--even weeds if they are not full of seeds. Adding commercial fertilizer is optional; the organic base is a requirement.

Q: We have raised beds with paths between. What is the best surface for paths? Grass needs mowing and uses water. Besides that, it creeps into the beds and has to be dug out. Bark and wood chips are hard to keep clean. Rocks are expensive. Eventually anything gets colonized by dandelions.

A: You have pinpointed the problems will all of these path materials. You did not mention black plastic and that is sensible. Years ago I thought that it would be the obvious choice--a low cost, efficient weed barrier. I tried it out, covering the plastic with bark to keep it from blowing away and to make the paths look more acceptable.

After a couple of years I tore out the plastic. Pebbles, feet and stiff stems had all poked holes through which weeds were growing. The plastic had folded and crumpled at the edges, leaving uncovered borders of grass and weeds.

There is no perfect material for paths and perhaps the best path is the one with fewest problems. Many of my paths have evolved into bluegrass, spread by seeds from the lawn. Some are bark or wood chips, with no underlayment. Neither is perfect, but neither is impossible.

I mow the grass paths regularly and I use pound-in edging along the side of the raised beds to slow down the grass which wants to move into all that rich soil next door. Weeds grow in the bark and have to be removed. My favorite tool for path maintenance is a battery-powered weed eater. Incidentally, I learned that the batteries last years longer if they are charged once a month all winter.

I also tried carpet scraps. I didn't like them either. I think that cost, appearance and maintenance all are important. As far as I know, the best path material may not be the same for all of us.

Master gardener Molly Hackett welcomes reader questions related to gardening, pest management, plants, soils and anything in between. Submit questions to mhackett@centric.net, call 406-961-4614 or mail questions to 1384 Meridian Road, Victor, MT 59875.