Recycle your fireplace ashes. Collect the ashes from your fireplace or wood stove in a bucket and leave it outside during the winter to mellow. In the spring, sprinkle the watered down ashes around your plants to increase the pH of the soil. If you want to cover an entire bed, sprinkle about 5 to 10 pounds of ashes for every 100 square feet of ground.
Learn about soil from a hydrangea. Sometimes figuring out your soil’s pH is as simple as looking out the window. If you have a hydrangea bush within sight. blue blooms indicate acid soil, while the pink blooms mean alkaline soil. Slightly purple blooms are just right, since they suggest your soil’s pH is perfect for most plants.
Indicator weeds reveal soil pH. If you can’t find the time to do an official acidity test, take a quick look at your pesky weeds to estimate your soil pH level. Dandelion, dock, horsetail, lady’s thumb, and sorrel thrive in acidic soil, while ironweed, pennycress, peppergrass, sagebrush, and woody aster thumb their nose at anything but alkaline soil.
Read your tomatoes for clues. Not sure about the state of your soil. Set some tomato plants in the ground and watch them grow. These blushing beauties can’t keep a secret. If the bottom leaves of the tomato plant turn yellow between the vines, your soil is low in iron. If they turn purplish brown, or the tomatoes have a black spot at the blossom end, you probably need to add some calcium. If the fruit ripens unevenly, with blotchy skin or a shoulder left green, you may need to add potash. And if a tomato plant is just pathetic and stunted, the soil is low in nitrogen.
Correct a mineral deficiency in your plants. When your plant refuses to grow and it’s bottom leaves turn yellow, it’s not being stubborn. It’s screaming I need nitrogen. Nitrogen is one of the three most important soil minerals and encourages plant and leaf growth. Add one of these ready nitrogen sources to the soil around your plant to fix the problem – well-aged manure, grass clippings, blood meal, hoof, horn meal, fish, emulsion, cottonseed meal, or soybean meal.
Give starved plants the jiggles. If the leaves on your plant turn yellow from the tip toward the stem, it’s in serious need of nitrogen. Give it a quick boost with a shot of unflavored gelatin. Dissolve an envelope of unflavored gelatin in a cup of hot water and add three cups of cold water. Then drizzle the mixture around the base of your plant before the gelatin sets. Repeat once a month but let your plant dry out between waterings.