If you’re planting a lawn or one of many different types of plants, you might wonder if you should use fertilizer on them and if so, what ratio. 5-10-10 fertilizer, which has 5 percent nitrogen, 10 percent phosphorus, and 10 percent potassium, is one of the most popular types of fertilizer for many plants, including trees, shrubs, fruiting trees, flowers, houseplants, and lawns. We’ll explain what 5-10-10 fertilizer is used for, how it benefits different types of plants, how and when to use it, and how to determine if you’ve used too much.
What is a 5-10-10 Fertilizer Used For?
A 5-10-10 ratio promotes healthy, robust plants in your garden throughout the growing season. It provides an extra dose of phosphorus and potassium for flowering ornamentals, fruiting shrubs, and vegetables.
However, when growing plants from seed use a higher nitrogen NPK, such as a 10-10-10 or a 20-20-20. Plants require more nitrogen at the beginning of their life cycle to develop robust root systems and foliage that will sustain them until maturity.
When buds are set, switching to a 5-10-10 NPK will encourage more blooms and fruit instead of just more foliage. This progression should also apply to new houseplant cuttings.
Trees and Shrubs
After a few years, non-flowering evergreens rarely require fertilization. But if they start showing deficiencies, a nitrogen-rich NPK will help stimulate new, healthy growth.
For flowering plants like magnolia, wisteria, hydrangea, and azalea, a fertilizer higher in phosphorus and potassium like a 5-10-10 can be introduced if a growing season goes by with few flowers.
The good news is that there are some low-nitrogen options that can increase or maintain soil acidity as well. Further benefits will be gained from using this fertilizer on acid-loving plants, which include azaleas, hydrangeas, berry shrubs, and plant species such as crape myrtle.
Fruit Trees
Citrus trees and shrubs require different amounts of different macronutrients at different times. 5-10-10 is extremely effective in producing abundant flowers and fruits and provides just the right amount of nitrogen for lush, green foliage.
This is especially true for smaller species when you need fertilizer for fruit trees grown in pots. To counter the heavy leaching of both water and nutrients that occur in pots, you should apply fertilizer with a 5-10-10 NPK regularly.
Dahlia and Other Flowers
For a plant to reproduce, it must flower. The increased phosphorus in a 5-10-10 NPK encourages healthy bud development, which leads to flowers and viable seeds.
Bulbs and tubers, like Dahlias, mature sooner, so buds and flowers appear earlier, resulting in vibrant, seasonal colors.
Dahlia fertilizers with a higher potassium content will not only boost drought tolerance and disease resistance in these plants but will also improve crop color.
Vegetable Gardens
Almost all vegetables need nitrogen, phosphorus, and potassium for roots, vigorous growth, and flowering, and some will do just fine with a balanced NPK, such as 10-10-10.
However, applying a 5-10-10 NPK fertilizer as soon as buds are set makes tomatoes juicier and more vibrant. Cucumbers and zucchini need special fertilizers to produce tasty, plentiful crops and more seeds for next year. Honeydew, watermelon, and cantaloupe are all ripe for summer fun.
Houseplants
A plant grown in fertile soil may not require as much nitrogen to maintain strong roots and healthy foliage. However, since they leech water and nutrients regularly, you’ll need to provide them with a steady supply of good quality houseplant fertilizer. In most cases, a 5-10-10 NPK will suffice.
The only exception would be flowering houseplants, such as African violets and bromeliads, which require more phosphorus for flowers and more nitrogen for vibrant foliage. These do best with a 7-9-5 NPK fertilizer.
Lawn and Grass
In lawns and grasses, phosphorus creates thick blankets of color and strong root systems. Despite this, they require nitrogen to maintain a vibrant structure that is resistant to extreme heat and drought.
Unless a soil test has revealed a high nitrogen content, a 5-10-10 fertilizer may not be sufficient. If it has, the low nitrogen ratio will prevent burning and root damage. If not, a slightly higher nitrogen option may be more appropriate.
How and When to Use 5-10-10 Fertilizer
A 5-10-10 fertilizer is the one to use when you need less nitrogen to prevent excessive foliage growth and need more potassium to promote bud and flower development.
In addition to providing plants with a small boost of nutrients, the relatively low percentage of NPK will also reduce the risks of root and leaf burn.
In fertile soil, triple 6 fertilizer will enhance the color and flavor of leafy vegetables such as broccoli and cabbage. It will also enhance the flavor of celery, kale, and asparagus, especially when planted in soil that only needs a small boost of nutrients.
Can you use too much 5-10-10 Fertilizer?
Too much nitrogen, phosphorus, or potassium can harm plants. Fertilizing plants too much can weaken them and make them vulnerable to pests and diseases. The symptoms of overfeeding include stunted growth, browning or yellowing of leaves, and bud drooping.
In case of doubt, a soil test will determine what nutrients are present in the soil. You can then compare those results with the needs of what you’re growing. By doing this, you’ll know what to add.
That’s what you need to know about 5-10-10 fertilizer. Before you decide what kind of fertilizer to use, test the soil to determine how much nitrogen, phosphorus, and potassium it already has in it. Once you know how much it has, you can decide whether you need to use a 5-10-10 NPK or a different strength NPK. If you’re lucky, you may not need any fertilizer at all. If you do need fertilizer, make sure you keep an eye on your plants to make sure they’re not showing signs of deficiency. With proper care, your plants will be healthy for the entire growing season.