Excessive nitrogen can cause your compost to heat up very quickly and even spontaneously combust, which becomes an obvious fire risk.
Ammonia. Compost piles smell like ammonia when they give off excess nitrogen (N) in the form of ammonia (NH3). This problem occurs most often if a composter has been adding high-nitrogen products. The smell signals that the pile has a surplus of nitrogen from too many green materials.
The ideal C/N ratio for composting is generally considered to be around 30:1, or 30 parts carbon for each part nitrogen by weight. Why 30:1? At lower ratios, nitrogen will be supplied in excess and will be lost as ammonia gas, causing undesirable odors.
Total nitrogen (N) includes all forms of nitrogen: organic N, ammonium N (NH4- N), and nitrate N (NO3-N). Total N will normally range from less than 1 % to around 5 % (dry weight basis) in most feedstocks and from 0.5 to 2.5 % (dry weight basis) in finished composts.
The rule of thumb is to combine 3 parts brown with 1 part green. Too much green will result in a mushy, smelly mess. And too much brown will slow decomposition. It doesn't have to be exact, but whenever you add a bucket of green kitchen waste, for example, try to add 3 same-size buckets of browns.
While adding compost to your soil can increase soil organic matter and improve soil health and fertility, too much compost can cause problems for the health of your plants and the environment.
Excess nitrogen can cause plants to grow excessively and develop overly succulent leaves and shoots, which promotes outbreaks of certain sucking insects and mites. Excessive nitrogen causes fruiting plants to produce relatively more foliage, reducing their fruit production and delaying fruit maturity.
Coffee grounds have a high nitrogen content, along with a few other nutrients plants can use. In compost, they help create organic matter that improves the ability of soil to hold water. It's best to add coffee grounds, not whole beans, to compost.
But as with everything, balance is key: too little nitrogen and plants cannot thrive, leading to low crop yields; but too much nitrogen can be toxic to plants, and can also harm our environment. Plants that do not have enough nitrogen become yellowish and do not grow well and can have smaller flowers and fruits.
You can lay mulch over the soil with too much nitrogen to help draw out some of the excess nitrogen in the soil. In particular, cheap, dyed mulch works well for this.
Eggshells are a green compost material. Here's the thing though - they don't contain much of either nitrogen or carbon. They may normally be mixed in with your other 'green' food waste from the kitchen, and as they tend to contain more nitrogen, they're placed in the 'green' camp.
Adding nitrogen-rich materials
The microorganisms in compost need both nitrogen and carbon to work. If there is too much carbon, the process will slow down. To speed up the process try adding 'greens' – items that are high in nitrogen, such as grass clippings or manure.
The passive composting methods are also known as cold composting, and you need to stop adding to the pile around when it should be done decomposing, which can take up to two years. In batch method composting – or hot composting – you need to stop adding to the pile until it has heated up and cooled entirely down.
Compost loses volume over time
The shrinkage does continue but slows down considerably as the compost becomes more stable. However, it will still slowly decrease in bulk over time. If you leave it too long, you are feeding microorganisms in the compost, rather than in the soil.
Banana peels are good fertilizer because of what they do not contain. They contain absolutely no nitrogen. While plants need nitrogen (remember the NPK on fertilizers), too much nitrogen will create lots of green leaves but few berries or fruits.
Egg Shells
Eggshells contain calcium, which plays a role in the strength and thickness of plant cell walls. Broken down egg shells on average contain 39.15 percent calcium, 0.4 percent nitrogen and 0.38 percent magnesium.
Banana peels are a great ingredient for your compost or worm farm, adding lots of nutrients to the organic recycling process.
These vegetables should NOT have added nitrogen: sweet potatoes, watermelons, carrots, beets, turnips, parsnips, lettuce.
Nitrogen makes plants grow. But too much of a good thing is a bad thing. When too much nitrogen flows to our bays, fast-growing plants out-compete and kill slower-growing beneficial plants. Decaying plants use up oxygen, which kills fish and other marine life.
As a rule of thumb, actively decomposing materials should be turned every three to four days. Materials with slowed microbial activity can be turned less often. In tumblers, turning two times a week resulted in higher temperature and faster decomposition than turning once a week or once every other week (Figure 1).
The rule of thumb for an active, hot pile is every three days until it stops heating up. Some over-enthusiastic composters rush out after a day and turn the pile. This is a bit too much of a good thing.
Three factors are usually to blame: poor aeration, too much moisture, or not enough nitrogen-rich material in the pile. A compost pile overburdened with materials that mat down when wet—grass clippings, spoiled hay, heaps of unshredded tree leaves—can become so dense that the pile's center receives no air.