Fertilizers provide nitrogen (N), phosphorus (P), and potassium (K) for your plants. This is the NPK ratio that you will see on bags or packages of fertilizers (ex: 2(N)-2(P)-1(K)). Make sure you know your plant’s needs before dumping just anything on them. Beware not to over-fertilize, which will harm your plants.
NITROGEN: "N” Boosts vegetative growth (leaves and stems), use more in spring when growth starts. Also use a high nitrogen based fertilizer for plants with more foliage than flowers, like houseplants.
PHOSPHORUS: "P” Stimulates flower and fruit production, use more when plants are in flower. Also use a high phosphate number fertilizer on plants that produce fruit or flowers.
POTASSIUM: “K” Enhances root growth, use more in fall when major root growth occurs. Usually the potassium in fertilizers is lower than the N or the P. If the plants need potassium then you may add it by itself.
Plants also need other nutrients (calcium, magnesium and sulfur) along with trace elements (boron, chlorine, copper, iron, zinc, manganese, etc.). These can be found in many mixed fertilizers or by themselves.
A soil test is beneficial before planting to see if the ground is missing any essential elements so you can correct the problem early.
Ex: Fish Emulsion and Seaweed Extract – supplies essential plant nutrients for green foliage, vigorous root systems, and solid plant structure. For indoor and outdoor plants.
Cow/Animal Manure – use as a top dressing for established plants. Raw manure is too hot for newly planted plants. Use bagged manure to ensure it’s been aged properly.
Peat Moss – combine with other soil amendments; use no more than ½ in a mix. It acidifies the Ph in soil and adds humic acid.