Recognizing Over-Fertilization Lawn Symptoms If you've accidentally spilled a bag of fertilizer before, you probably already know what fertilizer burn looks like. It shows up as scorched areas of the lawn (literally looked “burned”) and is typically crispy and yellow (or brown).
When you apply too much fertilizer or spill some by accident, the salt buildup can cause fertilizer burn. So, you'll see brown, yellow or streaked grass. This happens more often with quick-release fertilizers, which flood lawns with nutrients all at once.
The good new is that fertilizer burn is unlikley to kill off the existing lawn and with adequate rainfall or irrigation, it should regrow pretty rapidly.
Lawn burn from chemicals or heat usually looks the same. It will be a strip, patch or patches of yellow, tan or straw coloured grass that will appear within a day or so. The greater the over dose, the quicker it will appear.
The path to recovery for burnt grass can test a gardener's patience as patience is key. The duration of recovery hinges on the severity of the damage and the steps taken to rehabilitate the lawn. With diligent care, even the most damaged lawns can show signs of life within a few months.
Applying too much fertilizer to your lawn will cause the nitrogen and salt levels in the soil to increase rapidly, which can damage or even kill the grass. When this happens, it is known as “fertilizer burn” and looks like yellow and brown strips or patches of dead grass.
Damage from excessive fertilizer application generally appears as browning of leaf edges or leaf scorch. Soluble salts from fertilizers can pull moisture out of root tissues and cause wilting, marginal yellowing, and stunting.
The timeline largely depends on the burn's cause. Moderately-burnt grass needs about one week to grow back, while heavily-burnt grass takes about one month to reestablish. The recovery time for burnt grass depends on the type of grass on your lawn and the leading cause of the burn.
Lawn Repairs for an Over-Fertilized Lawn
Aeration and overseeding can be one way to get new grass growing in your lawn. If you still have some growth and the damage is mostly in patches, this process should work well to restore lawn areas.
If the dried, burnt areas are limited to small bare patches in the lawn, then you may be able to encourage growth there by watering them generously and fertilizing those areas. However, be aware that fertilizing grass during hot weather can make grass less tolerant to heat.
It depends on the fertilizer. Some lawn foods perform better when you water them in right after applying, while others—such as some weed-and-feed products—need to be watered a day or two after fertilizing. It all comes down to this: Check the product directions on the bag—they'll tell you when to water.
Prune all of the dead foliage off of your affected plants. If you're treating burned grass, reseed the area with new grass seeds over the damaged brown grass. You'll have to wait to see if the affected areas can recover, but pruning damaged growth away is a good start.
Chlorophyll is produced when your grass has enough nitrogen in its system, which gives it that desirable green color. However, when it's yellowing, it could be a sign that it is lacking in nitrogen. Fertilizers provide this nutrient, along with others, to the soil, which helps to promote healthy, green grass.
Depending on the level of damage done to your grass, you may be able to reverse the effects of fertilizer burn and help your lawn grow back lush and green. The important thing to remember when fixing fertilizer burn is that you need to reduce the amount fertilizer left in the soil.
Most homeowners should fertilize their cool-season turf in March, then May, then from September to October. However, UC IPM recommends that lawns in the Sierra area should be fertilized from May to June and August to September.
Fertilizer burn. Fertilizer burn symptoms appear soon after fertilizer is applied. You'll often see grass blades dry from the tip and yellow, brown, or scorched stripes following the application pattern. If you act fast, turfgrass can recover in a few days to weeks.
Signs You Over-fertilized Your Lawn
But days or even weeks later, you'll notice the yellowing dead patches or stripes in the areas that got too much fertilizer. You might notice more subtle changes sooner. Maybe you're not seeing new growth. Or maybe just the tips of your grass blades are yellow or brown.
When it comes to lawn fertilizer, timing is crucial. In addition to looking at the weather forecast, you should consider whether your lawn is wet or dry. Ideally, you should apply a fertilizer treatment to a dry lawn when there is no rain forecasted for the next couple of days.
Watering Adequately: Flush out excess fertilizer by watering the lawn thoroughly. Root Inspection: Post-watering, check for new root growth to gauge recovery success. New Grass Planting: If necessary, prepare the ground for and plant new grass.
Still, the lawn is not “burned”. What takes place in the presence of excess nitrogen is simply that the salt content in the fertilizer is pulling the water from the grass plants, leaving them to quickly dry out and turn brown, looking “burned”.