We have had an ongoing debate about zone 2 garden weed management. We've tried mulch (grass clippings mostly), and, though it worked well, it's hard to get enough clippings for a garden the size of ours to effectively control weeds, and it's pretty labor intensive. We heard lots of raving about cover crops and their benefits to the garden, etc., etc. So last year we let our native enthusiastic purslane volunteers go crazy, and it was great for the garden: we got lots of tasty purslane and the plants helped with evaporation problems, nutrient accumulation...but it was a bit messy since the lambsquarters, bindweed, and pigweed also tried to help out. Well this year we decided to try out more "official" green mulches. So we planted clover, turnips, buckwheat, and field peas, and then planted our pumpkins and butternut squashes into the mix (I will forgive all of you more experienced natural gardeners for laughing uproariously at this point, this post is for all naive newbies like us). Everything went gang busters, lots of nutrient accumulation, lots of weed control (sort of, the lambsquarters were pretty impervious), except the pumpkins and squash looked a bit anemic and weren't growing as well as expected...hmmmm.
Fast forward two months...crazy messy garden, lots of turnips, some scraggly field peas, and a few small on the verge of death squash and pumpkin plants. Very sad!
So we pulled all the turnips, peas and buckwheat, left the struggling squash plants to continue fighting the good fight, and got an enormous bale of old straw for mulch.
Now for the happy ending: the squash and pumpkins did a remarkable job of making up for lost time. In fact, we got a squash harvest not too far off of normal. We are very impressed! The straw is working well (although it's not out competing the bindweed, not much does), and the clover we left on the paths looks lovely. Whew!
Learnings:
Important semantic definition: cover crops are not ground covers. Cover crops are meant to be tilled in as green manure, not used as perpetual ground cover around your garden plants. If you want ground cover, stick with purslane.
Old straw is cheap and works well as mulch.
Clover works well as a low-growing, green, nitrogen fixing, mowable groundcover for paths, don't know how it would do over the whole garden and after this summer we're a little scared to try it out.
We should do experiments on small portions of the garden instead of on the whole darn thing!
Writer's apology: unfortunately, we do not have any pictures of our turnip harvest. Our enthusiasm for recording the proceedings for posterity was at a pretty low ebb at the time, so you'll just have to imagine the whole tragic event.