It's easy to make your own super-premium plant food!
Q: I love your show, and your devotion to compost. Could you help us with some "Composting 101"? What should we include? Vegetable scraps, teabags, coffee grounds? And we never stir; should we? Also, I love mulching with fall leaves. Do you have a good suggestion for shredding them?
- ---Lorraine in Healdsburg, Northern California
We recently moved to this area and planted a garden this spring. We used Miracle-Gro once a week and ended up with lots of tomatoes and cucumbers, but also lots of bugs and weeds; and many of our plants didn't produce anything. I know we need to compost, but how do we begin? We have magnolia and oak leaves and lots of kitchen scraps. Do we put them in a wire bin, or just pile them on top of each other in a certain place?
- ----Toni in Woodville (East) Texas
Back in Michigan, I learned that mixing coffee grounds into the leaves in our basement window wells created an excellent and reliable source of fishing worms. Now we live in NJ, and I have been taking coffee grounds from the office to apply to my tomato garden. I figure increasing worm activity and soil acidity is not a bad thing. Do you agree?
- ---Gary in Browns Mills, NJ
A: Well, thanks you three; and all the others who've emailed recently to ask for simple, basic composting advice. And yes, that includes Coffee Ground Gary in New Joisey, who is indeed wrong to be dousing his tamatas with old grounds alone. By themselves, those grounds are simply a high-nitrogen fertilizer that will make plants grow big, but will not help them grow more fruits and flowers. Just the opposite in fact; too much nitrogen and you get big plants with few flowers.
By mixing those coffee grounds with decomposing leaves when you were back in Michigan, you were making high quality compost—which the worms colonized when it was finished. If you wish to maximize your earthworm action, simply shred up and store lots of leaves this fall and then mulch your tomatoes with those shredded leaves next Spring; earthworms LOVE to live under a shredded leaf mulch.
Those leaves are also what's missing in Lorraine's compost equation. As I explain in the brand new, just-published "Mike McGrath's Book of Compost" (Sterling publishers; available wherever books are sold; makes a great gift!), leaves are the most important part of a compost pile. In fact, leaves are the part of the pile that becomes the finished compost. Kitchen scraps, spent garden plants and such are simply food for the organisms that will turn those mineral and nutrient rich leaves into garden gold!
If all you do is shred up big batches of leaves and nothing but leaves and let them sit until the Spring they will become high-quality compost all on their own. That's right—without anything being added or mixed in. In warmer climes, most of that leaf pile will become compost by Spring. In moderate to cooler climes, the top will still be shredded leaves, but there should be a generous layer of rich black compost on the bottom, all ready to feed your plants and prevent disease. No muss, no fuss.
My favorite way to shred is with a leaf 'blower/vac' on its reverse setting. The built-in shredder in such a machine will reduce the volume by at least a factor of ten, allowing you to store lots of leaves for future mulching and compost making. Remember: These precious ingredients only 'fall' once a year but you'll need a big stockpile for season-long mulching and compost mixing. (And yes, those leaves must be shredded; whole leaves make a terrible mulch, and resist composting.)
But, of course, many people begin composting because they want to recycle their kitchen waste. Unlike shredded leaves, however, if you just pile up kitchen garbage, you'll end up with a pile of kitchen garbage. You need at least four parts well-shredded leaves to each part green waste to get good compost. If you are not willing to shred up lots of leaves, take the advice I offer in the brand new, just-published "Mike McGrath's Book of Compost" (Sterling publishers; available wherever books are sold; makes a great gift!), and use a worm bin instead. Those worms will gladly devour your scraps and give you high quality compost in return.
If you are willing to mix that waste in with your shredded leaves, however, you'll be able to make much larger amounts (And make good use of all those leaves!) Containing the raw ingredients in a wooden slatted bin with lots of airflow, a commercially made composter or big wire cage will move things along much more quickly. I use my tomato cages for this; they make great compost containers and will conveniently be empty by the time my tamatas are ready to be caged next Spring.
Any non-meat kitchen waste—yes, including eggshells, coffee grounds and tea bags—can be used to make up the green portion of your pile; just remember to make sure there's four parts shredded leaves to each part green waste. The more you chop things up, the faster it will move along; same with mixing and turning. But as long as the vast majority of the pile is well-shredded leaves, it will become compost. And when you feed your plants that rich black compost instead of a nasty chemical fertilizer like Miracle-Gro, you'll have fewer pests, more productive plants and better tasting food.
As I explain in my brand new, just-published "Mike McGrath's Book of Compost" (Sterling publishers; available wherever books are sold; makes a great gift!), those are just the basics. To learn everything you could possibly want to know about the subject, pick up a copy of my brand new, just-published "Mike McGrath's Book of Compost" (Sterling publishers; available wherever books are sold).
Did I mention it makes a great gift?