Dear Miss Floribunda,
Last month you advised “Uber-Organic” that home compost is usually well-balanced for the vegetable garden. It would be a lot less expensive than purchased compost or plant food and would be a great way to get smelly kitchen garbage out of the house. I’d like to try it but need to have a few questions answered before I go to the trouble.
1) What are the best things to use, and what things should not be added? a) I am aware that meat scraps would attract rats but what about clean bones — those already boiled for soup, for example? b) What things guarantee the balance you mention?
2) What is an inexpensive container for compost? a) Please don’t suggest anything I have to build unless very simple. b) Does the city have any restrictions on what can be used?
3 ) How long does it take before usable compost develops? a) Is there any way to help it along? b) Can I start now, or wait till next spring?
If there’s anything I’ve forgotten, please let me know. Thank you.
Cautious Composter on Crittenden Street
Dear Cautious Composter,
Now is an ideal time to start a compost pile. For one thing, the City of Hyattsville is offering free state-of-the-art composting bins by GEOBIN. Not only will you save time and money, you won’t have to worry about violating any city code, you will cut down on the time needed to have usable compost and you’ll greatly expand the range of what you can compost. The bins are made of lightweight but rugged plastic, are 36 inches high and expand from 2-feet to 3 1/2-feet in circumference. They can hold up to 216 gallons (14 bushels) of compost. They not only retain heat and moisture well, but their open-weave design allows for needed ventilation and drainage. For information about how to get one, please contact Colleen Aistis at 301.985.5057 or firstname.lastname@example.org. She tells me the demand is great, but the supply will be renewed if the city runs out of them. They are also inexpensive to buy online.
You can start right away, using grass clippings from your mowing, and in time to add the leaves that will soon be falling from your trees. Capability Green, of the Community Garden, asks me to caution you — cautious as you are — against adding any seed-bearing weeds or diseased vegetables. You, yourself, are aware that meat is out of the question, and although I confess I am tempted to say yes to clean bones for the calcium they provide, they can’t be used because they would attract scavengers of all kinds. Egg shells, however, are not an attractant and provide calcium. Their alkalinity can be offset by the addition of acidic coffee grounds and tea leaves. Banana and avocado are particularly good for adding much needed phosphorus and other essential elements. Some people advise against this if you plan on using the compost to grow potatoes because the peels might harbor potato blight. In well-rotted, turned compost this is highly unlikely, and potato blight is rare in our area because our soil is not alkaline. Carrot and cucumber peels are good, but onion and citrus peels can harm earthworms. You definitely want earthworms, and they are attracted to compost. Do not add oils or fat.
Along with the green waste of fruit and vegetable table scraps, grass clippings and green leaves, experienced composters advise adding brown waste: paper, dead leaves, twigs and sawdust (if not from chemically treated wood). The green waste provides nitrogen, and the brown adds carbon and aids aeration. As autumn is coming soon, you will have lots of leaves to add. If you mow the leaves into fragments first and moisten them, the volume will quickly reduce, and you can continue to keep adding them till hard frost. Begin watering your compost bin again in spring, and remember to turn it from time to time. This is called cold or passive composting, and it generally takes about two years to create usable compost — probably less in a GEOBIN. If you’re in a hurry and want to take the trouble, you can do what is called hot composting. You need to add much more more green material, which is high in nitrogen, and even processed manure (no pet waste) or high-nitrogen chemical fertilizer. Leave out corn cobs or branches, or other materials slow to break down. Aside from getting usable humus faster — perhaps within six weeks — you don’t need to worry about grass and weed seeds, which the heat will destroy. However, hot compost is a worm killer, and I can’t emphasize too much the importance of earthworms. It can also be a potential fire hazard if it heats too rapidly. You would need to get a compost thermometer to monitor the heat.
There are some other caveats. Aunt Sioux advises against newspaper in any compost pile because of possible toxins in the ink, but shredded cardboard is fine, and is a good source of high-carbon brown material. I am assured by other gardeners that most modern newspapers use soy-based rather than petroleum-based inks, but you might test first to be sure. Slide your finger over the surface of the paper and rub — if your finger darkens with residue you know that the ink contains petroleum oil, which never completely dries. Also, you can visit the newspaper’s website which often will give the composition of the ink. I personally use my shredded papers in compost for my rose garden but make separate compost for the vegetable garden. If there are toxins in these scraps, they have not harmed the bushes themselves, but I would not want to take a chance on having them contaminate any plant intended as food. I never use shredded junk mail, the paper of which is often glossy — an indication of highly volatile compounds in its composition.
If you would like to know more about composting as well as other important ecological initiatives being encouraged by the City of Hyattsville, please come to the next gathering of the Hyattsville Horticultural Society at the Emerson Street Food Forest on Saturday, Sept. 8. Dawn Taft, Hyattsville’s city arborist, will give a tour you will not want to miss. The address is 4515 Emerson Street, and we meet at 10 a.m.