From cranberry pomace to potting mix

Cranberries, and especially the sauce and the juice, may not be as green as you may think

by Michael Smith (Veshengro)

Both cranberry sauce, which is a staple at many Thanksgiving meals and also for the Christmas turkey in Britain, and cranberry juice, thought to ward off urinary tract infections, require that the skins of the cranberries they are made from, be removed.

So, if that is the case, what happens to the skins? For the most part, they are shredded and end up as organic waste deposited in a landfill – five tons of them in fact from Ocean Spray alone.

One man, a waste hauler by trade, decided to see what could be done about using the shredded skins, referred to as pomace, for something other than landfill waste. It turns out the answer may be yes as researchers at the University of Massachusetts have determined. They have found that pomace, when composted is quite similar to peat moss, a staple of potting mix and over the past few years pomace has been sold as mulch to some local wholesale mulch companies.

Several commercial flower growers in Massachusetts have agreed to be guinea pigs for the University of Massachusetts researchers and to experiment with various potting mixes containing pomace to see whether it is beneficial or not. So far the results are positive, with the winner being that of a 50:50 mix of peat moss to pomace. Too much pomace added to the mix makes it too acidic for most plants.

The other, simple answer, would be, and no research would have been required which may have cost a lot of money, tax dollars more than likely, to simply compost the pomace with other organic matter.

Once properly broken down and mixed, during the process of composting, with other matter, in the same way as coffee grounds are used, it just becomes simple compost for use in the garden.

It is amazing how often researchers try to reinvent the wheel.

On the other hand it is time that all that pomace was recycled into compost rather than dumped into landfill where the process of decomposition will add to emission of methane gas, a greenhouse gas far more dangerous than carbon dioxide.

Then again this methane gas could be used as natural gas for heating and cooking and for powering electricity generating plants. All that is required is to draw it off the landfill sites. Too simple, I guess.

© 2012