Weeds That Cry Out "Compaction and Crust"
Chicory and bindweed are telltale signs of compacted soil. That's why you often see the blue flowers of chicory along highways. Chicory also is common in gardens where beds have been left empty or, worse still, where soil has been worked when it's wet.
If your weeds indicate compacted soil, plant a cover crop of white lupines and sweet clover. They have roots as strong as those of pesky chicory, and they help to break up the soil. At the same time, these cover crops replenish the nitrogen levels in the soil.
Although a hard crust on your soil's surface can prevent many vegetables and flowers from breaking through, it doesn't deter quackgrass or mustard family weeds at all.
If weedy mustard is flourishing in your garden, pull it up and plant closely related brassica crops such as broccoli, cabbage, cauliflower, and choy instead. They can push through crusty soil with ease. Replace quackgrass with a fast-growing grassy cover crop (such as rye) in fall, then till it under the following spring. The cover crop will loosen the soil and choke out the weeds.
To aerate and lighten crusty and compacted soil, add compost. Prevent future problems by working your soil only when it's dry.
Photo: (cc) Joost J. Bakker/Flickr