Plastic mulch tends to warm the soil. It's best used on warm-season vegetables, such as tomatoes, melons, peppers and squash. If soil gets too hot in midsummer, put a shallow layer of organic mulch on top of the plastic. Pulling weeds Don't underestimate the effectiveness of pulling weeds. It's good for your plants and your figure, too.
Young weeds can be very easy to pull, especially during or just after a rain.
It's best not to compost weeds, unless you're sure your pile heats up enough to not only compost the plants but kill the seeds. Preventing weeds from going to seed will save you many future battles. A single dandelion plant can produce 15,000 seeds in one year, and each seed can survive up to six years in the soil. Each purslane plant can produce more than 52,000 seeds, and each can survive up to 30 years. It's clearly in your best interest to stay ahead of the weeds.