Compostable: Yes, but…
Ivy is normal plant material, so it will definitely compost. The problem however lies in ivy’s ability to sprout and regrow from a small fragment. Obviously we don’t want this in our compost.
To avoid this, people have suggested a number of possibilities. One option is to set it aside and allow it to completely dry out before adding it to your compost. And even then, cut it up into small 3-4 inch sections.
Another option is to get it composting on its own for the initial stages, perhaps with the cut up ivy in a black plastic bin bag. And only when it has started to decompose, add it to the normal composter.
Compostable: Sort of…
Moss is a very persistent beast, and putting it in a normal composter seems to be no guarantee of killing it and decomposing it.
Like all greens things, strictly speaking it should break down, but many people report that the moss is regrowing a very short time after the compost is spread around your plants. In fact it can appear decomposed but within a day or two it is green and growing again.
Perhaps this is all down to not getting enough heat into the compost, and a high enough temperature might actually kill off the moss. But if you want to avoid the possibility of spreading moss to your currently moss-free garden plants, then maybe throw the moss in the garbage instead of the composter, just to be safe.
Compostable: Yes (but with some notable exceptions)
Most weeds from the garden can be safely added to your composter. In general, the heat produced from a good decomposing compost should be sufficient to kill the seeds of most weeds. After all, you don’t want to be introducing weeds to your flower beds by using your compost.
There are a few exceptions, where the heat produced may not be high enough to kill off all the weed seeds. In particular, avoid adding any dandelions, bindweed, couch grass, Japanese knotweed, creeping buttercup, horsetail, ground elder or lesser celandine to your compost.
To avoid problems with other weeds, perhaps only add the fresh leaves of the weeds and throw the roots away (although the roots and the small amount of soil on them will contain loads of active organisms that would help get your compost going). If in doubt, maybe throw any flowers and seeds of weeds away as well.
Category: Green / Brown
If you have cut flowers in your house, they will be a fine addition to your composter.
Depending on how woody the stalks of the flowers are, you might want to cut the stalks into smaller lengths. The woodier the stalks, eg roses, the more ‘brown’ you might consider them. Also, the smaller the pieces, the quicker they will decompose to create your compost.
Mushroom scraps and leftover stalks from the kitchen and the mushrooms you might find growing in your garden can all be put in your composter.
Mushrooms can easily grow on your compost, the spores are released from underneath the mushroom cup. The way to avoid this is to make sure that there is sufficient heat in your composter to kill off any mushroom spores.
Grass clippings are a fantastic activator for your compost and adding a little of this will help get things going quickly.
It is really important to not get carried away and add too much grass. Grass on it’s own will compact down, excluding oxygen from the decomposition process and turn into a dark, smelly slime. To avoid this, add grass in moderation, and ideally try to let it dry out a bit before adding to the composter. If you think you have added too much grass, add more ‘brown’ material as soon as possible and give it a good mix through.
Peppers, like most other vegetable scraps, can be put in the composter.
If these are kitchen leftovers, there will likely only be the central core left with the seeds and the stalk attached. Or if they have started to go off before you had a chance to use them, perhaps you will be throwing the whole pepper in the composter. Either way, this will be fine and these will decompose quickly.
Potato Peelings and Skins are a great addition to the composter.
Some people may be worried about potatoes sprouting in the compost. This can start to happen if you are adding whole potatoes or large pieces of potato. However, if there is sufficient heat in your composter, the heat will kill off the sprouting potato shoots.
This problem will not happen if you are just adding potato skins or peels. They will decompose quickly without sprouting.
Tea Bags, both used and unused, can be put in to your composter. These can help add good structure to your compost.
Depending on the brand, the bag itself may or may not completely break down, even after a few years. Avoid adding nylon-based bags but other natural fibre-based bags should be fine. As long as you get sufficient heat into your composter you will maximise your chance of it decomposing. Your best bet is to give it a try, and if you’re not happy with the result, maybe tear open the bags before putting in the composter.
If you are fussy about your compost, you might want to remove the tiny staples (if there are any) from your tea bags.
You should avoid pouring a cup of tea, or tea from the pot, straight into the composter, only because of the risk of introducing too much moisture.
Banana Skins are an excellent thing to put in to your composter and a good use of a common throw away item. They are a great source of organic material and valuable nutrients for your compost. Some people cut them up first to help speed up the composting process, others put them in whole, but it really doesn’t matter either way. They will quickly and easily decompose in your composter or compost heap with no problems.
Alternatively, banana peels are an excellent source of nutrients for roses. Some people bury the banana skins a few inches under the ground, around their rose bushes. Roses seem to benefit greatly from the nutrients provided by the banana skins and produce a good healthy show of flowers. And it’s a good simple natural way of fertilising your roses without having to resort to chemical fertilisers.
But if you are doing this, you should be aware that it may take a bit longer to decompose the banana skins if they are buried beside your roses. Decomposition works best and quickest in the presence of air, and burying the banana peels under the soil deprives the decomposing microbes of the essential oxygen. They will break down eventually and release their nutrients, but it may be faster to add them to your general compost heap or composter, allow them to break down, then add the compost to the roses.