Question. Mike: Do you happen to know if it's possible to buy good
quality compost in bags? I'd like to use compost in my garden, but only seem to be able
to find manure and topsoil in bags at the garden center. I've seen places that will
deliver loose compost by the cubic
yard, but I don't have a driveway for them to dump it. Love your show!
Answer. Thanks, Peter! Now if you have access to good quality
yard-waste compost in bulk, my first suggestion is to see if it can be delivered to a
friend's home nearby or some other mutually agreeable site where several gardeners could
share both it and the cost. You'll find lots of info on buying bulk compost in this
previous Question of the Week.
Otherwise, the basic
answer is yes; there are high quality bagged composts out there. But as with
most things gardening, the devil—or angel—is in the details. Here's an
updated version of how I addressed this topic in my 2006 book, "Mike McGrath's Book of
Compost" (still in print, kids; get your copy today!)
If we're
talking about the cheap, wet, heavy, generically bagged stuff without a lot on info on
the label sitting out baking in the sun at a big box store, it's not my first choice.
(Or second, or third, or…) It shouldn't be anyone's choice, really. The labels
and names on cheap bags of "Maybe Compost" are generally somewhere between
non-existent, confusing and extremely misleading (as the materials inside the
bag often are as well). And this low-rent spread has probably been anaerobic inside that
bag for a long time.
If it's all you can find
(and it isn't; there's always mail order if you truly live in a horticultural
supply desert), two esteemed experts I interviewed for the book, Ohio State University
Professor Dr. Dan Herms and University of Maryland Professor Emeritus Dr. Frank Gouin
suggest you buy a sample bag, take it home, open it up and give the contents a 'quack'
test. (If it looks like good compost, feels like good compost and smells like good
compost, it might actually be good compost.)
If it
quacks loud enough, go back and get some more, empty the bags out, mix the contents
together (ideally with some REAL home made compost or some of the premium stuff we'll soon mention) and
let it sit awhile before you use it.
"Square Foot Garden"
author Mel Bartholomew once offered a variation on this method during one of our
conversations. He suggested you visit a number of different stores, buy one
each of their bagged composts, bring them home and evaluate them. Then go back and buy a
couple bags each of the best ones and mix them together—again, ideally with some
backyard compost or stuff from a premium bag.
READ COMPLETE
ANSWER
BUT you should only do this if you have a high level of
internal honesty. If anything tends to be 'good enough' because you already
bought it or it's all you could find at the very first store you visited (and your idea
of 'good compost' includes slimy things that don't stink really bad), forget
about it. You might get lucky, but that's what you'd be. In other words, the
odds are against you, and if you feel unable to make the decision with any certainty,
cut to the chase and search out some high-quality premium bagged compost
instead. You and your garden will be MUCH happier.
Some
of the brands I've used and been happy with include "Gardener's Gold" from Garden's Alive;
"Coast of Maine" (available in larger independent garden centers from at least New
England down to the Washington DC area); and "Leaf Gro", packaged by the state of
Maryland's superb yard-waste recycling program—something I'd like to see more
states imitate.
There are also two 'specialty' bagged
composts I've used: "Chesapeake Blue" (composted crab waste and sawdust) and "Chesapeake
Green" (composted poultry manure and bedding). Both are rich in Nitrogen; and Chesapeake
Blue has the added advantage of being rich in chitin (pronounced "kite-in"), a
substance that occurs naturally in seafood shells, survives the composting process and
makes the soil it's applied to toxic to destructive nematodes. In the North, bad
nematodes generally only attack a few ornamentals, like boxwoods. But down South, root knot nematodes are a destructive pest of
MANY plants. Search for chitin-rich composts, my Southern friends, and you will
be happy.
(Note: The beneficial nematodes you purchase to
control pests like beetle grubs and fleas in the soil are not harmful to
plants. But they are nematodes, and so could also be killed by lots of chitin.
Just to be safe, avoid seafood composts if you're applying these helpful creatures to
your soil.)
There are probably dozens of other high-quality bagged
composts available across the country—these things tend to be regionally produced
and packaged. But you should know them when you see them. They will cost a little more,
have a lot more info on the label and basically give you a warm and fuzzy feeling all
over.
One final note (hey—my producer just keeled over
laughing; I wonder why?), peat moss is NOT compost. It is a popular component
in seed-starting
and potting
mixes, and a natural antibiotic that prevents damping-off and some other diseases.
But it's too light in weight for many applications, contains little to no actual
nutrition, and can radically lower the pH of your soil whether you want it to
or not. Now don't get me wrong: I like peat moss. I use peat moss. Peat moss is a friend
of mine. "But I know compost; and peat moss is NOT compost."
One OTHER final note (oh—THAT's why she
keeled over), Dr. Gouin wants to stress that 'dried' products like Milorganite and
dehydrated manure are not compost. Composting is a complex process by which raw
ingredients are changed by living organisms and processes. Drying is not the
same—not even close. Dried something-or-other can't do all the wonderful things
that living compost does.