Most Landscape Plants are Fertilized Once a Year

Q.  I live in the Anthem community in Henderson NV at 2900 feet and have a large variety of plants watered with drip emitters. I typically fertilize three time a year with a local nursery product. I also apply EDDHA iron chelate as needed if a shrub shows signs of yellowing. Comments?

One fertilizer application in the spring of each year is enough for most landscape plants. Some exceptions are lawns, vegetables, annual flowers and specialty shrubs like roses.

A.  Mineral fertilizers for home landscapes are all the same, whether you get them from a local nursery or not. I select a mineral fertilizer based upon price and the three numbers on the outside of the bag.

This is called a "starter fertilizer". Why? Because the middle number, phosphorus, responsible for helping new roots to grow is highest. Phosphorus also helps promote flowering so it is also used as a rose fertilizer and tomato fertilizer.

The last of the three numbers, potassium, should always be high. The first number, nitrogen, encourages growth and greening of the plant and disappears with watering. The middle number, phosphorus, encourages flowering, rooting and sticks around in the soil longer after an application. If there is any fertilizer needed by plants later in the year it’s the first number, nitrogen.

Blood meal, fertilizer made from the blood of animals, is high in nitrogen; usually 12%. It also has iron in it but the numbers quoted for this fertilizer when sold as a mineral fertilizer is 12-0-0.  It is not "organic" unless it carries the organic label. Even though it is made from blood, it is not considered an "organic" fertilizer.

One application of fertilizer in the early spring of each year is all that is required for most landscape plants. Exceptions are lawns, vegetables, and “show plants”, like roses that produce a show of flowers to enjoy. Even fruit trees grow well with one application of fertilizer in the spring of each year. Winter tender plants, like most citrus and bougainvillea, are fertilized only once in the early spring, avoiding fertilizer applications after the middle of summer.

All that being said, it’s always best to repeat applications of fertilizer in small amounts all through the growing season. It’s not necessary, but according to research it’s best. this is the selling point made for fertilizer injectors like EZ Flo.

EZ Flo fertilizer injectors are not really fertilizer vernri type fertilizer injectors rather than the very expensive but very exact fertilizer injectors. Theas types of injectors are exact enough for most homeowners but may not be exact enough for commercial greenhouse growers who need more precise application of chemicals to the irrigation water.

For plants that like continuous feeding such as vegetables and “show plants”, I like to use rich compost as a fertilizer in the beginning of the year and then follow up with very light nitrogen applications the remainder of the year when needed.