Clover is widely used as a cover crop as it is fast growing, enriches soil nitrogen and in addition to choking out weeds, it protects exposed soil from erosion and retains moisture. Clover is also fast spreading, a characteristic which aids it out compete weeds, but which may also be problematic as it begins to encroach on your vegetable patch and compete with other plants for resources. However, with careful management, it can be a very effective mulch.
The danger of clover choking small plants can be avoided by planting the fruits/veggies first and waiting a little longer to sow the clover seed, allowing the crop plants a head start. Also, planting a short stemmed variety such as New Zealand clover will help prevent this competition. This variety should be very effective on walkways but will naturally begin to encroach into the vegetable patch. You can let it continue to spread around larger plants or remove it. Fortunately, clover is easy to pull back by hand and you can manage walkways with a mower. The clover should also be effective in rows between plants such as corn, wheat, tomatoes etc and depending on your location, it will continue to grow year on year, providing good winter cover or it will die back in the heat of the summer and need replanted.
Clover is widely used as a cover crop.