Start Composting

By Steve Reiners, Professor and Chair, Horticulture Section, Cornell University, Cornell AgriTech. This is part of a series of columns that he wrote about vegetable gardening during the pandemic that ran Spring-Summer 2020. Read more articles from 2020 | Read later articles in this series.

August 7, 2020

What do you do with your kitchen waste?  Vegetable and fruit peels, old salad, coffee grounds, apple cores and cherry pits?  I sure hope you don’t throw them in the garbage to get carted off to a landfill.

And what about the weeds you pull out of your garden, grass clippings or soon to be falling autumn leaves?   Don’t bag them and haul them to the curb. Compost them instead and you’ll reap the benefits in next year’s harvest.

Why compost?

Composting allows all these organic materials to slowly rot, creating a fantastic soil additive that will feed not only your plants but all your soil microbes as well.  Plus, it removes the nearly 30 percent of the waste stream that now goes to landfills.  Composting is a win-win situation.

What you need

New gardeners may be intimidated by the idea of composting, but it’s really easy.  You essentially need three things. 

High carbon items called “browns”

  • Paper and cardboard
  • Fall leaves
  • Even dryer lint!

High nitrogen items called “greens”

  • Fresh grass clippings
  • Coffee grounds (with filters)
  • Fruit and vegetable scraps from the kitchen
  • Weeds and other garden waste


  • The third item is one even veteran composters often forget.  Just the right amount of water will ensure microbes thrive and the ingredients break down into a rich, friable material.

What not to compost

Some things that should not go into the compost include kitchen wastes like meat, fish, bones, dairy, eggs, and bread. These can attract unwanted rodent visits.  Living in Geneva, I’m fortunate to have a facility that I can bring those materials to where they can be professionally composted.

Even though manure from some animals like horses, cows and sheep are fine, keep pet waste from dogs and cats out of your pile.  These may contain parasites and pathogens that would likely survive the backyard compost process as you typically don’t get a high enough temperature in your pile to kill the harmful organisms.  Waste from pets like rabbits, hamsters and guinea pigs can be used.

People often ask if they should compost diseased leaves and plants.  To be honest, I compost just about all the plant material from my garden. If I didn’t throw some diseased plants in mine, it would be a pretty small compost pile.  By now, everything is showing some disease symptoms.

About the only thing I might keep out is any tomatoes or potato plants that were infected with late blight.  But the good news is, as of right now, the disease is not present in New York, so no worries. 

Getting started

Getting started is easy.  You can buy some premade composters at the store or check with your local solid waste recycling center. But you can just start piling up materials in a shady part of the yard.  And forget about the instructions about one layer of browns followed by a layer of greens.  You will find it will work just fine by throwing in whatever you have at that time.

You can get finished compost in as little as two months. Or it may take up to a year.  It depends on many factors.

Smaller is better.  Shredded, chopped up things break down quicker.  Also aerate the compost by turning it with a pitchfork.  The more air, the happier the microbes and the quicker they break things down.  And add a few shovelfuls of compost from a previous pile or even some garden soil.  This adds microbes that feast on the organic material.

As you inspect your pile, you will notice that the bottom layer often is ready before the upper layers where you have the freshest material.  That’s why I love using a two bin composter.  I can simply take the top layer off and place it in the second bin and then get down to the rotted material at the bottom.

Simply take this finished compost and apply it evenly over your bed in the spring and work it into the soil.  Or sprinkle some around your plants in midseason to give your plants a boost.

Unfortunately, not every town allows for backyard composting. So before you start, check to see if yours does.  If it doesn’t or you feel you don’t have room, you have other options.  You can bury the waste in your beds where it will slowly rot.  Add coffee grounds right to your potted plants. I’ve even known some people that put their kitchen waste in a blender and then pour the “smoothie” right on the soil.

This week in the garden

Downy mildew is in the area and affecting cucumbers as well as melons and squash.  Symptoms include pale green to yellow spots on leaf surfaces that later turn brown.  This week’s rain could worsen the problem,  For gardeners, resistant varieties are your best bet.  Fungicides can be used but need to be applied before you see the disease.