What are some good combinations of different types of household materials that can be used to make nutrients for plants?Why and how?
The best thing for garden plants are your vegetable table scraps and peelings to use in a compost heap. Composted vegetable scraps, egg shells, and peanut hulls have trace minerals that enrich the soils. Combine with lawn trimmings and perhaps a scoop full of barnyard waste, you will have "black magic" right in your own back yard.
Powdered milk contains calcium that most plants need. Mixing 1/4 cup of milk powder in a gallon of water will contain sufficient amounts of calcium for broccoli and cruciferous vegetables.
Epsom salt contains magnesium which tomatoes and peppers need in order to be fruitful. 2 Tablespoons of Epsom salt in 1 gallon of water in a monthly dose will fertilize tomatoes and peppers with this essential trace mineral.
Vinegar is something that is useful in small amounts to kill fungus and mildew that grow on plants. Household bleach is also something that might be useful to kill powdery mildew, but it can also damage plants.
Other materials that are beneficial to plants are coffee grounds, coffee filters, along with any undrunk coffee, or tea, for that matter. Newspapers, cardboard, banana peels can join them. Also, water from any fish tanks in the house provides additional nutrients since the fish are performing bodily functions in the water.
A good way to recycle stale spices and herbs is to include them as part of the mulch for plants. Potatoes that have stayed too long in the bin and are now growing sprouts are also excellent candidates for this recycling. Dry moldy bread can go, too. Orange juice and apple juice that have sat too long in the refrigerator are worth recruiting as well.