We receive questions about fertilizing almost daily so I thought I would review the subject and add some suggestions.
Most fertilizers list the ‘big three’ nutrients on their label: those being nitrogen (N), phosphorus (P), and potassium (K) in that order. For most gardens a balanced general-purpose fertilizer with numbers that are all the same such as 4-4-4 is the best approach for general plant health and ease of use. If growing a vegetable garden where the fruit is developed from a flower, like tomatoes, peppers, cucumbers, etc, a fertilizer with less nitrogen and more phosphorus like a 4-6-3 is a better choice. If your garden is mostly leafy vegetables like lettuce, kale, and other greens, then a fertilizer with more nitrogen is called for. General-purpose fertilizers typically contain some of the ‘minor’ nutrients as well like sulfur, iron, calcium, magnesium and copper. Organic fertilizers often have the advantage of containing beneficial microorganisms that break down the nutrients making them available for the plants. These fungi and bacteria are the ‘good guys’ and help ward off bad fungi and bacteria. Organic fertilizers depend on those microorganisms to make the nutrients available so it’s very important to have them in the soil. Inorganic fertilizers will work just as well too and are actually taken up by the plant faster however they do not benefit the soil like an organic fertilizer.
A common question people ask is how often to fertilize. That can vary depending on your soil and plant material. For hanging baskets and containers we generally say to fertilize once a week with a liquid, all-purpose fertilizer. For your flower beds one application of granular or liquid fertilizer per month may be sufficient. For vegetable gardening you will want to make an application during the first month and then taper off through the summer.
If you haven’t taken a look at our June events on our website or facebook page be sure to check in and see what’s happening here at Ashland Greenhouses. Our next event is our “Heat Lovers Class” June 8th from 10am-11am, reservations required so call to save a seat.