Beginning late summer and through September and into early October is a great time to fertilize many plants. This includes lawns, young trees, shrubs that need to grow more leaves and groundcovers that need to spread and cover.
August is an ideal time for gardeners to give their plants a boost into the later stages of growth. Many people who are just learning how to garden at home overlook the benefits of fertilizing their plants.
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.
Timing: Apply fall lawn fertilizer once between August and November, right before winter hits, 6 to 8 weeks after the summer feeding.
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.
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.
This means the temperature can't be below freezing, so the task is typically handled sometime in early November in most places in the north. If you live in a warmer area, however, December can be a great time to fertilize your lawn.
Even evergreen trees and shrubs do not require fertilizer this time of year. The list of plants benefiting from fall feeding is a short one. Feed cool-season lawns such as bluegrass, fescue, and ryegrass in October and November for lush winter cover. Fertilize spring-flowering bulbs at planting time.
In general, try your best to apply it between September 1 and October 15. The farther north you live, the earlier you should apply it. The goal is to have at least one month of active grass growing weather remaining before winter takes its grip.
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.
Apply Low-Nitrogen Fertilizer
Whereas nitrogen-rich fertilizers are appropriate for the early springtime green-up and growth, as we just mentioned, they can cause further stress to lawns in the summer and even cause burns. That's why low-nitrogen fertilizer is a great option for summer lawns.
Michigan State University Extension advises to not fertilize perennials in late summer or early fall. This may cause the plants to flush-out additional growth that will not harden-off in time for an early winter freeze.
Choosing a lawn fertilizer blend
A complete fertilizer with a high ratio of both nitrogen (N) and potassium (K) is essential for root growth, winter hardiness and disease resistance. An ideal fall fertilizer blend will have a nitrogen to phosphorous to potassium (N:P:K) ratio of 24-4-12.
Fall is the best and most important time to fertilize your lawn because: Fall's morning dew delivers moisture to help turf absorb the fertilizer. The grass has a chance to build stamina before a chilly winter. Supporting root growth in fall leads to a healthier, greener lawn in spring.
Perennial flowers are a bit different than annuals. They generally require less fertilization and since they often slow down growth in autumn to prepare for dormancy, fertilization should be avoided after late summer.
Vegetable gardeners can fertilize their garden beds about once a month with a quick-release fertilizer or about once a season with a slow-release fertilizer. Some gardeners prefer to feed their flowers and plants with a liquid-soluble plant food once every one to two weeks.
Once you've selected a fertilizer (make sure you use an organic one!), you'll need to apply it about once every two weeks for container grown plants. This assumes that you're growing in a high quality, compost rich potting mix that will help retain nutrients.
These tend to be species that grow fast and bloom a lot, including most annuals, fruits, veggies, roses, and hydrangeas. These plants appreciate being fed about once a month during their growing season with a general-purpose liquid fertilizer.
When To Fertilizer Your Lawn in the Fall. The best time to apply your last fertilizer application is between August 15 and October 1. Ideally, your last lawn feeding should take place six to eight weeks before the average first frost in your area.
Fertilizer should not be applied to already frozen ground since it will not do any good to the lawn. Worse still, the unabsorbed nitrogen and nutrients will likely leach back into the water system. The best time to apply winterizer is in late fall, about three weeks before the ground is frozen.
Winter is a time of rest for many plants. Lights is life to plants, and in fall and winter, when there is less sunshine than in summer, most plants grow less vigirously. In their semi-dormant state, plants need less fertilizer. Most foliage plants can go four months (November to March) without feeding.
I have just always thought that you fertilize when a plant is actively growing to help it along or right before it starts actively growing. But fertilizing in winter (or late fall depending on your climate) can actually offer nutrients to strengthen roots (that do often continue to grow in winter despite dormancy.)
Don't apply winterizer too late—Generally, winter fertilizer should be applied in November or earlier, depending on your climate. Try to avoid applying in early December, as the nutrients within the formula may not take hold in time to protect the grass from the harsh conditions.
Winterizer Fertilizer
Winterizer helps the roots of the grass absorb and store nutrients. The roots continue to grow until the ground eventually freezes. These nutrients are stored and ready to go, so when spring comes around, your lawn hits the ground running.