I try to fertilize my lawn at least twice a year, every spring and fall. The application of fertilizer in spring prepares the turf for vigorous growth and removes yellow or brown spots from harsh winter conditions. In the fall, the grass starts to slow blade growth and focuses on strong root development, and a different fertilizer, one low in nitrogen, is needed.
It can be frustrating to have to buy different fertilizer products for different months; it’s the same grass, after all, but not doing so could lead to other turf problems. When you consider that common weeds are different in both spring and fall, and herbicide use varies accordingly, you can see why these products aren’t necessarily interchangeable. But what exactly happens if you use fall weed and feed in the spring?
Can Fall Lawn Weed and Feed be Applied in the Spring?
Lawn weed and feed is a formula that kills selective lawn weeds while feeding your turf grasses the exact nutrients they need. In order for these grass products to be effective, they need to be applied at the right time with the right weather conditions and temperatures; otherwise, they won’t work as well. Fall weed and feed should not be used in the spring if you want to get the most out of the formula.
Using fall lawn weed and feed can still help a yard more than not feeding it at all. There will be no real harm to the grass, assuming it is mostly healthy and balanced, just from using fall fertilizer in spring. In some cases, using fall weed and feed can be beneficial for your lawn if you need a low-nitrogen fertilizer or post-emergent pesticide early in the year.
Sometimes, certain flowers, like dandelions, survive the winter and need a post-emergent herbicide. Fall weed killers usually affect weeds that have already sprouted and can help kill those unsightly stragglers earlier in the season. The granules of weed and feed are also time released and can release nitrogen and other nutrients into the grass slowly. Using drop spreaders and shooting granules to where broadleaf weeds survived the winter can help you maximize your late spring fertilizer and weed-killer application.
What Nutrients Do Lawn Grasses Need?
A healthy lawn needs lawn fertilizer, and applying it correctly helps your turf use the nutrients more efficiently. Lawn care involves getting nitrogen and other macro and micronutrients into your soil so your turf can benefit all year round. Most grass types grow actively from spring to fall, and fertilizing with spring feed and autumn lawn feed is important lawn care activity.
| Nutrient | Season Needed | Amount |
| Nitrogen (N) | Spring | High |
| Phosphorous (P) | Fall | High |
| Potassium (K) | Spring, Fall | Moderate |
Spring Nutrients
In the spring, active growth begins as the sun heats up the soil and the grass breaks dormancy. Once temperatures rise, adding a spring fertilizer can give new grass sprouts and newly awakened turf a huge boost. The main goal of rapid spring growth is to get the nutrients to the roots quickly and fill in any bare spots of the lawn before the summer heat. Quick-release spring lawn fertilizers high in nitrogen are needed in the spring to achieve these goals.
Fall Nutrients
In the fall, you are going to want to apply a slow-release nitrogen fertilizer. As the grass goes dormant, it will not need much nitrogen for active growth. However, as the winter ends, the nitrogen content near the lawn roots will be high enough that new growth can start. To make the lawn stronger, use a lawn root-enhancing autumn lawn feed.
Common Fall and Spring Lawn Weeds
In both spring and fall, certain weeds will invade your turf and try to choke out your carefully selected grasses. Letting weeds get a root hold in spring or fall can cause your turf to suffer. In spring, new weeds have yet to sprout, and in the fall, they are at their most vulnerable for selective herbicides; choosing your weed-killing products carefully can help keep your lawn uniform with less use of poisons.
| Weed | Season Found | Treated With |
| Clover | Spring | Pre-emergent |
| Dandelion | Fall | Post-emergent |
| Invasive Crab Grass | Spring, Fall | Pre or post-emergent |
Spring Weeds
Weeds like clover and invasive grasses can start to spring up by late spring. In order to get ahead of these pesky plants, it is a good idea to lay a pre-emergent herbicide. Many springtime lawn feed and weed formulas include these weed killers. Post-emergents, the herbicides more commonly found in autumn weed and feed products, are not effective for weeds that haven’t yet broken ground.
Fall Weeds
In the fall, the weeds that remain have the potential to drop their seeds and make many more invasive plants next spring. A post-emergent herbicide commonly found in fall weed and feeds can selectively kill mature broadleaf and other non-turf weeds without hurting your blades of grass. Combine using these when using autumn lawn feed products with proper mowing and watering schedules to reduce the spread of weed seeds in the fall.
Other Ways to Maintain a Lawn In Spring?
Most lawn fertilizer products work best when combined with the correct lawn care activities. A green, magnificent and healthy-looking lawn does not come about without a lot of work and TLC. Below are some of the top steps a lawn expert takes to prepare their turf in spring.
Watering Schedule
Depending on your climate, you will either get more or less moisture from above as the summer approaches. If you live in a place where most of the moisture comes in the winter, you will need to begin setting your watering systems to pick up the slack as the days get longer and hotter. If you have rainy springs and summers, now might be the time to turn off the sprinklers after your dry winter season. Make sure your grass is getting enough water without becoming soggy or waterlogged.
Aeration and Dethatching
For grass to grow, it needs to get nutrients and water all the way down to its roots. Most of the water, whether from rain or the sprinklers, comes from above. The slow breakdown of lawn debris during the cool winter months can build up as thatch and block moisture absorption. Lawns can also become compact over the winter months from leaves and snowfall.
Using a dethatching rake and pulling up all the partially decayed grass can help improve nutrient uptake by your turf. Using a core aerator or other tools can further reduce compaction and improve the moisture and nutrient retention of your soil. The water retention and absorption rate of your lawn increase with proper maintenance, and erosion can be prevented during heavy downpours.
Mowing Schedule
Grass roots grow deeper the taller the blades of grass reach. As we mow the lawn more frequently during spring, the grass has a chance to grow stronger, fuller blades. Mowing the grass low at the start of spring and then keeping it steady through summer can help encourage vigorous growth all year long.
Some grasses need very little mowing once the summer approaches. Warm-season grasses that go dormant but do not die in the heat and drought can go weeks without being hit with a mower. Make sure to help these turfs build strong roots and dense mats by mowing them frequently through the early spring.
Weed Control
If you used an autumn lawn feed with post-emergent herbicide, you shouldn’t have too many weeds remaining in your lawn. What weeds do remain can be pulled up or treated with a selective herbicide. You can easily pull weeds from a wet lawn, so spring is a great time to remove any unwanted plants and resow grass seed in winter-damaged areas.
Spring is also the time that new weed seeds start to sprout. Birds, squirrels, and the wind all bring tons of new plants to your lawn every year that want to grow in your rich soil. Using a pre-emergent herbicide can stop these weeds from germinating and crowding out your grass seed. Weed control in the spring is crucial for a stress-free lawn all summer long.
Pest Control
The warmer temperatures also invite pests to enter your lawn and start to feed and reproduce. From insects like termites and ants to larger rodents like squirrels and wild animals, pests on your lawn can do serious damage. Treating for likely pests like beetles and mosquitos can help keep your outdoor times more pleasant while reducing grass issues.
Additional pest control methods like trapping moles or repelling foragers can keep your grass safe. Dogs and other animals that like to use your lawn as a bathroom can also be discouraged with fences and motion-activated sprinklers. Keep animal and pest damage away from your yard by taking the right steps in spring to protect your turf.