Some gardeners rototill each year out of habit or tradition, thinking it’s the right or necessary thing to do. Others may avoid rototilling to avoid disturbing the soil structure.
Benefits of rototilling
Rototilling is one method of turning up the soil before you plant your garden. It’s also an efficient way to distribute fertilizer. Colorado State University Extension says that regular tilling over time can improve soil structure.
In the fall, leaves and other organic matter can be rototilled into your garden’s soil to improve it, according to Colorado State University Extension. Add a couple of inches of top dressing — composted materials or peat moss — and rototill it in after leaving it on top of the soil for a couple of weeks.
Disadvantages of rototilling
Rototilling can destroy soil structure. Plant roots need air spaces to grow, but tilling too much closes those spaces. Farm and Dairy online columnist Ivory Harlow adds that tilling can deplete the soil’s nutrients.
Turning up soil through rototilling can disturb worm burrows, bringing them up to the surface where they will die, University of Illinois Extension explains. Worms play a vital role in the garden because they provide nutrients for the soil and also aerate it.
In addition, rototilling too early in the season, before the soil temperature warms up, can cause the soil to compact. This will make it difficult for summer watering to be effective, according to Oregon State University Extension.
To rototill or not to rototill
Do you need to rototill your garden? Here are some questions to ask yourself before you break out the tiller this spring:
Why do I want to rototill?
If this is the first year for your garden, rototilling is a good idea for loosening up the soil and getting it ready for planting.
If your garden’s soil has good tilth from last year and you don’t need to add amendments, don’t rototill this year.
Rototilling as a weed control method may only help with annual weeds but not perennial weeds. Rototilling will make certain perennial weeds increase in number, according to University of Minnesota Extension.
Instead of rototilling as a method of weed control, consider using a hoe or your hands to turn weeds under. Using newspaper or black plastic on top of soil can discourage weed growth, as suggested by Farm and Dairy online columnist Ivory Harlow. If you rototill to control weeds, additional methods, such as herbicide application, may be necessary.
If you’re adding compost to your garden’s soil, you can do so with a shovel or a spading fork instead of rototilling, Oregon State University Extension says.
Has my soil been tested? Do I need to work fertilizer into the soil?
Test your garden’s soil. Once you have the results of your soil test, you’ll know how to amend it properly and you can determine if you need to rototill.
If your soil test indicates that you need to add fertilizer or lime, rototilling is one method of doing that. University of Vermont Extension says that you may need to rototill to a depth of 8-10 inches to work in the recommended amendments.
What is the water content of my soil?
If your soil is too wet when you rototill, you run the risk of ruining the soil structure. Working with soil that’s too wet can create soil compaction.
Determine the moisture of the soil. Roll a handful of soil into a ball. Bounce it off of your hand. If the soil sticks together, it’s too wet. If it crumbles with a little pressure from your fingertips, it’s dry enough to be worked, Oregon State University Extension explains. If your soil contains clay, tilling when the soil is workable is crucial.
Have my seeds already been planted?
Be careful tilling if you’ve already planted your garden. You don’t want to disturb plant roots with a rototiller. If you’re going to till after you’ve planted your garden, don’t till deeper than 2 inches below the soil’s surface.