Welcome to summer! Or at least I think it's summer since southern California is having a very strong “June Gloom” period that started before June and has touched July. You folks up north have had some pretty hot days though. That got me to thinking about solarization – the non-chemical process where soil is heated to a temperature that kills weed seeds (in this case) – by using the sun's energy.
Solarization is effective for controlling a number of different weeds species and on the surface (no pun intended), it's a pretty simple technique. Make the area smooth, wet it up, cover with clear plastic (be sure to tuck it in on the edges), and walk away for 4 weeks. It's also something that can be done on small spaces (although I don't think I would go much smaller than 25ft2) to many acres, provided you have the right equipment. Optimally, you would apply the plastic during the hottest part of the year but if you are in the desert, no need to wait until the daily temps hit 110, you are good to go pretty much anytime in the summer. For the rest of us mortals, generally August to early September will be fine.
Clyde Elmore, Weed Science Specialist emeritus, wrote a great blog about solarization about 4 ½ years ago so I'm not going to repeat it here. However, I invite you to take a look at it and also check out the newly revised Pest Note Soil Solarization for Gardens & Landscapes to prepare yourselves should you choose to try it out this year.
