Weeds do not grow in old-growth forests, it’s not their environment. Like all organisms, weeds grow well when they are within their particular ecological niche, one that supports their needs the best. This brings us to the theory of Ecological Succession – the observed process of change in a species structure of an ecological community over time. This describes how environments change due to life processes and thus supporting differing kinds of organisms in the same place over different periods of time.
Lets begin with an inhospitable environment, slowly colonized by hardy pioneering plants capable of surviving and thriving in that terrible place. Through their actions of living and growing, the conditions to support other plants are now met and new species move in and eventually replace the pioneering ones, as the conditions are no longer conducive to them. This processes continues over and over again until a stability of sorts is met, called a climax community, like an ancient old-growth forest. Ecological succession can take many hundreds or thousands of years to occur naturally.
Plant succession can be seen just about anywhere. Take you family on a hike through a natural area. Starting in the parking lot, a very inhospitable environment, you can see early pioneering plants peeking through cracks in the pavement and growing through gravel. As you enter the trail you can see very hardy plants growing on the well trodden trail. As you pass through a field you can see grasses and wildflowers succeeding to bushes and small trees and at the forest edge tall trees take over and the plant species change yet again. In time, the field and parking lot may too become forest.
Plant succession can also be witnessed in the garden, converting a section of your lawn to a vegetable plot is a good example. The lawn is a sort of Climax Community, while the combined actions of the lawn mower and Weed & Feed keep the conditions static. Till up the grass and you have now caused a drastic change in the environment, no longer suitable for lawn grass. Initially your garden soil may be somewhat rich that first year and weeds are wimpy and easily swept away. The next year however may be different and your weed pressure increases. Now the garden is being heavily attacked by very noxious weeds such as bindweed and quack-grass. No matter how hard you control them they just seem to win, and by mid-summer gardening is fast becoming a real chore. You now consider applying an herbicide to remove those pesky weeds once and for all, but they return the following year intent as ever to take over your lot.
Most garden weeds are lower succesional plants, meaning that they are the pioneer plants capable of growing well in disturbed, unbalanced and inhospitable grounds. These weeds can be found anywhere people have seriously disturbed the area by stripping away the topsoil, applied toxic compounds or mined the soil of its limited minerals. Observe the plants growing along the sides of a road, a farmers field, the front lawn or your own garden plot. Most fruits and vegetables on the other hand are higher successional plants found naturally growing only in the deep rich soils near streams and rivers.
For robust and successful weeds, all you need to do is observe the conditions that allow the weeds healthiest growth and practice soil management in a way that continuously converts soil to dirt. Be sure to break up the ground frequently with lots of digging and tilling. Limit and destroy the microbiological life by applying herbicides, pesticides and other toxins. Use plants to mine the soil of nutrients and minerals and never return them. Apply fertilizers and compost excessively. Remove all plant residues, including grass clippings and leaves, and if necessary throw them into the garbage. And always make sure the soil stays bare for as much of the year as possible.
That is the irony. The misconception is the conditions that allow for healthy vegetable growth are the same conditions that allow for healthy weed growth. That just isn’t true. If your weeds are overpowering your garden, your soil conditions are not suited for vegetables. If however your vegetables are overpowering your weeds, then you’ve got one awesome garden.