Vinegar -Some plants, such as azaleas, gardenias and rhododendrons need acidity to get soluble iron. If you live in a hard water area, these plants suffer from excess lime, causing the leaves to turn yellow. To compensate for this, add 2 tablespoons of cider vinegar to a quart of water. Pour a cupful or so around the base of the plant every two or three weeks until the yellow goes away.
Soft Drinks - Soft drinks containing citric acid control development of microorganisms that can block the plant’s water conducting vessels. A molecule of water can move from the base of a 24″ cut rose to the petals in 30 seconds or less. The cells of the stem of a rose, which carry the water, are like a handful of soda straws. The liquid can only be drawn up the ‘straw’ as long as the straw is clean. The Michigan State University’s Department of Horticulture recommends mixing a solution of one part water, one part soft drink, then adding 1/2 teaspoon of chlorine bleach to each quart of solution.
Lemon Juice – Get more mileage from your cut flower arrangements with this homemade preservative: Use two tablespoons of fresh lemon juice, one tablespoon of sugar and 1/2 tablespoon of household bleach, added to 1 quart of water. Place flowers in this mixture.
Epsom Salts and Borax - Home gardeners who raise melons often complain about a flat taste, even if the vines get plenty of sun and plant food. Quite often the trouble is due to a lack of magnesium in the soil. University of Maryland College of Agriculture tests showed that muskmelons could be sweetened by spraying the vines with a solution of borax, Epsom salts, and water. Use 3 1/3 tablespoons of household borax, plus 6 1/2 tablespoons of Epsom salts, in 5 gallons of water. Spray foliage when the vines begin to “run”, and again when the fruits are about two inches in diameter.