After a long growing season, your trees start to wind down their activity in fall. Fertilizing your trees in fall will help them build up their energy stores to carry them through winter.
Many experts accepted this timing for years. And although early spring is a good time, new research indicates there is an even better time. Now a majority of arborists consider late September or October a great time to consider a fall fertilizer for trees and shrubs.
For all trees and shrubs.
If needed, the best time to fertilize is late April or early May, or late fall once plants are dormant.
Fertilizing trees in the fall is important timing, particularly for deciduous trees, as many key nutrients are used up earlier in the year, producing leaves and fruit. To replenish those lost nutrients and prepare your trees for the next growing season, tree fertilization is key.
Young, rapidly growing trees should be fertilized annually to promote rapid establishment. Mature trees may need fertilization every two or three years to maintain good foliage color and vigor.
Fertilizing in the fall helps plants be hardier when the temperatures drop. We also recommend applying fertilizer in the late fall, toward the end of October or early November. This application will catalyze one last frenzy of root growth and really give your plants some staying power through the cold months.
The exact timing for when you should fertilize your lawn in the fall varies based on weather conditions and climate zone. In most regions, October is not too late for fall fertilizer, and you can even put fall fertilizer down in November in many places.
Fall Fertilizer Timing
For the majority of cool-season lawn owners, apply fertilizer anywhere from September through early November. The further north you garden, the sooner you'll feed your lawn. Fine-tune the timing for your locale by talking with your local extension service or garden center.
Water helps "activate" your fertilizer. It helps move the granules deep into the thatch where it starts to break down so that it can be soaked into the root system. So rain after a fertilizer is a GOOD thing. The issues is when we get too much rain over a short period of time.
If necessary, spring and fall are the best times to fertilize trees and shrubs. Fall applications should be made after leaf drop (mid-October through November). Spring applications should be made in late March or early April before the trees and shrubs begin to leaf out.
We recommend waiting 24 hours after fertilizing to water your lawn, which will give the fertilizer time to settle. After the 24 hours are up, it's important to give it a good soak—not just a quick spritz with your hose—to activate the fertilizer and help the critical nutrients absorb into the soil.
While the best method for determining exactly how much fertilizer is needed is a soil analysis conducted by a laboratory, most cool-season grasses require 2 to 4 pounds of nitrogen per 1,000 square feet each year, and a majority of this nitrogen should be applied in two fall applications; one in September and the other ...
That being said, applying autumn lawn feed in the spring will not necessarily hurt your lawn, but it will not provide the type of results homeowners typically look for in the spring. There is more to consider when making the choice of what lawn feed to use.
While this fall lawn fertilizer dose is important, an application at the end of October or early November is essential. At that time, apply a fertilizer with a formula of 13-25-12. The push of phosphorus will stimulate root growth through November and even into early December.
You should fertilize your lawn a day or so after a light rain or using a sprinkler. This prevents the application from being washed away. The moisture gets your soil damp and ready to receive nutrients. Do not apply fertilizer before or after heavy rains.
The November fertilizer application is the second most important time for cultivating a cool season bluegrass or tall fescue lawn, with September being the most important application. The November application helps the lawn flourish in several ways.
A “complete” fertilizer — one that supplies the macronutrients nitrogen (N), phosphorus (P), and potassium (K) — is often recommended. A fertilizer analysis of 10-8-15 means the fertilizer has 10 percent nitrogen, 8 percent phosphorous, and 15 percent potassium.
Just like fertilizing your lawn, the most important fertilizer you can apply to your lawn is nitrogen. Nitrogen will help your trees grow throughout the winter and into the spring. It is the most commonly used fertilizer on trees, grass and other plants.
Q: When in the fall is it best to fertilize my trees and shrubs? A: Wait to fertilize until late fall, once plants are dormant. Don't fertilize trees and shrubs you just planted or re-planted. Older trees may need fertilizing less often.
While liquid fertilizers will still provide nutrients to your trees and shrubs as a quick fix, it will drain through the soil much more quickly—especially if your plants are on top of a slope or hill.
High-nitrogen fertilizers are known for causing huge growth in plants, which is why many types are rich in nitrogen or include it as the main component. Fertilizers high in nitrogen will also restore bright green hues to your foliage.
You can safely apply up to 1 pound of nitrogen per 1,000 square feet per year. A 20-pound bag of 10-10-10 fertilizer, enough to cover 2,000 square feet, contains 10 percent or 2 pounds each of nitrogen, phosphorus, and potassium.