Tips for Fertilizing Garden Plants
Ensure your garden is full of flourishing plants by providing them with the correct nutrients as and when they need them. Get the feeding right, and they will respond with healthy leaf, fruit, and flower growth.
There is a wide range of plant foods available, from manure and compost to liquid, granular, and powdered feeds. Some are inorganic—man-made; others are organic—derived from plant and animal waste.
Some feeds have equal proportions of the three major plant nutrients (nitrogen, phosphorus, and potassium, represented by the symbols N, P, and K), which promote all-around healthy growth. Others have a higher percentage of a particular nutrient; these are designed to encourage root, foliage, or fruit development. Specialty granular and liquid feeds are also available for specific plants or purposes, like orchid, tomato, citrus, and bonsai fertilizer, and ericaceous and sequestered iron fertilizers.
It’s important to get feeding just right. Too little results in weak growth, while too much promotes soft sappy shoots that attract the attention of aphids, become vulnerable to frost damage, and may need support. A careful look at a plant should tell you if it is lacking an essential nutrient. Leaves that yellow at the edges and between the veins show signs of iron deficiency.
Granular or powdered fertilizers are mainly used to feed established plants in beds or borders or to boost soil fertility before planting. Apply in early spring, scattering it around established trees, shrubs, and perennials, or working it in to broad patches of soil. If you need to treat a large area, divide it into square yards (meters) with canes for more even distribution. Always wear gloves when handling dry fertilizer.
Added to the soil or mixed into compost in powder or granular form, these fertilizers feed plants gradually over a period of time. They are particularly useful if you are short on time, as only one application is needed. Follow the instructions given on the packet for the correct application, and wear suitable gloves when handling the fertilizer.
Fast-acting liquid fertilizers can be applied to soil or compost, once diluted, or added to a sprayer and used as a foliar feed—this is useful if a plant is suffering from a nutrient deficiency and needs a pick-me-up. Liquid feeds that are high in potash are ideal for improving yields of fruits and vegetables, such as tomatoes, peppers, and strawberries, or to extend the display of flowering annuals. Kelp is a good tonic for garden plants. Dilute concentrated feeds according to the packet instructions, or use the more expensive ready-mixed feeds.
Simply digging bulky farmyard manure into the soil improves its structure and water-retaining ability, encourages beneficial organisms, and adds nutrients. Ideally, apply well-rotted manure in the fall, either as a 2–3 inches (5–7.5 cm) deep mulch to established beds, or dug into large areas being prepared for planting in the spring.