Question:
I’m new to gardening and wondering why container plants need to be fertilized so often. If you buy good plants, use good soil, and take care of them, why is fertilizer still necessary? Also, why does 0-10-10 help plants bloom? Won't they bloom on their own?Answer:
- That’s a great question. I’m sure many gardeners have wondered the same thing.
- Plants require nutrients to grow and thrive; without them, they struggle and eventually die. One of the functions of roots is to absorb nutrients. These nutrients are then transported upward throughout the plant.
- Nutrient depletion in containers is rapid because every time you water, which is frequently, water carries them away as the container drains. It’s important to recognize that container plants have perfect drainage, unlike those planted in our clay or adobe soil, which drains poorly.
- Also, the roots are restricted to a predefined area, the pot size, while those plants in the ground have plenty of room to expand beyond their canopy.
- Soil microorganisms are also present, absorbing organic matter and converting it into nutrients. Over time, the volume of soil in containers decreases as it is replaced by roots, whereas this is not the case for plants planted in the ground.
- The three primary elements necessary for plant growth are Nitrogen (N), Phosphorus (P), and Potassium (K), also known as NPK. There are ten or more secondary elements, like Boron, Iron, Sulphur, Copper, Magnesium, and others, needed in lesser amounts.
- Nitrogen is necessary for growth and lush green foliage. It leaches quickly from soils because it is a mobile element, so it needs to be replaced frequently.
- Phosphorus and Potassium support fruit and flower production, aid in general plant hardiness, and remain longer in our soils.
- The nutrient/fertilizer analysis is on every bag of fertilizer and is expressed as a percentage. The first number is always Nitrogen (N), the next is Phosphorus (P), and the last is Potassium (K). On the back of every fertilizer bag, you'll find a detailed listing of all the elements, including the secondary ones.
- Some plants fail to bloom when they grow too vigorously, while others are unaffected by the growth cycle. Light and temperature are two other strong influences on flowering. Low or no-nitrogen fertilizers, such as 0-10-10, help plants bloom and are applied to Bearded Iris, Citrus, and others during the winter months.
- Gardeners switch to 0-10-10 once the desired size is reached for Azaleas, Camellias, Fuchsias, Tuberous Begonias, and other flowering plants to maximize color.
- Today, we’re spoiled for choice, with many types of fertilizers to choose from, including time-release, organic, water-soluble, and synthetic. They’re all right answers, but which one is the best? Fertilizing is a nurturing gardening activity, so some gardeners like to do it often. Others not so much.
- I prefer time-release fertilizers. I only have to feed a couple of times a year to keep plants thriving. I don’t know what’s best for you, but the Nursery Professional at your favorite garden center is a resource to answer the question.