If you want a lush, green lawn, your grass may require more nutrients than what the soil, sun, and water have to offer.
Fertilizer can provide that extra boost to your lawn during the summer and get your grass looking even more healthy.
But while fertilizing might be great for your grass, it can cause big problems for the other plants and flowers around your garden.
Will Grass Fertilizer Kill Flowers?
If you are using a grass fertilizer that does not contain any pesticides or herbicides, then it will not kill your flowers if a little gets around them.
The problem arises for your flowers when you contaminate them with weed and feed fertilizers that are also “selective” herbicides.
Selective herbicides kill broadleaf weeds like chickweed and clover, but will not harm the grass on your lawn.
Unfortunately, these weed and feed products cannot tell the difference between broadleaf weeds and your beautiful flowers and will kill them too.
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Why Does Weed And Feed Kill My Flowers?
Weed and feed products or fertilizers that combine selective herbicides kill certain plants while providing others with nutrients.
Grass weed and feed fertilizers are able to identify and attack broadleaf plants while feeding grass plants the nutrients they need to grow lush and green.
When these types of fertilizers come into contact with your flowers, it identifies them as broadleaf plants and kills them by stopping their metabolic processes.
Why Grass Fertilizer Is Important
Some lawns require that fertilization boost if they are to grow to their full potential.
Fertilizer boosts grass with a mix of Nitrogen (N), Phosphorus (P), and Potassium (K).
These three ingredients help with rapid growth, lush green color, a healthy root system, and disease resistance.
As time passes, soil naturally loses many of the essential nutrients it needs to grow to its full potential.
So If you’re really after that lush, green lawn, you may need to replenish those lost nutrients with fertilizer.
But, as mentioned earlier, the problem for your flower beds is many fertilizers are now adding in weed killers.
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How To Fertilize Your Grass Without Killing Your Flowers
Each fertilizer or weed and feed comes with specific instructions.
Your first port of call should be to read the instructions carefully and follow them.
Check That You Are Using The Correct Type Of Fertilizer
Always check that the fertilizer you are using for your lawn is the correct one for the type of grass you have.
Some weed and feed come as a spray, while some come in granular form.
Either way, you will need to be careful around your flowers.
Don’t Let It Spread Too Far
Granular forms use a spreader.
Whether it is a walk-behind or a ride-along behind the lawnmower, be sure you have the spread set at the appropriate level so you can control where it goes.
The bag of fertilizer granules should tell you what that setting should be.
For the best results and to keep your flowers alive, do not spread right up to the base of the flower bed, shrub, or tree.
Cover Your Flowers With Plastic
If it is a flower bed, you can try covering it with plastic until you are done spreading the fertilizer and then uncover your flowers when finished.
That way, any overspread will hit the plastic and stay away from your flowers or shrubs.
The plastic will work for both liquid and granular fertilizer.
Don’t Spray Fertilizer When It Is Windy
If you are using a liquid fertilizer, do not spray it when the wind is blowing more than 2 or 3mph.
Even that slight breeze can cause it to blow where you do not want it to go.
One other word of caution on fertilizer, do not over-fertilize your lawn.
It could kill the grass instead of making it grow stronger and lusher.
What To Do If Grass Fertilizer Gets On Your Flowers
If you overspread or you have a spill in the flower bed, the first thing to do to scoop up as much fertilizer as you can.
Your perennials should survive as long as they didn’t take too much herbicide but annuals may have a harder time.
If you find any damaged shoots, you’ll need to cut them back – then feed, mulch and give lots and lots of water.
Feed, mulch and turn on the irrigation and let the water run as long as the ground can hold it.
Be careful about runoff, though, as it could contaminate nearby water sources.
The watering will flush salts away from the plant’s root system and prevent them from dying.
They may turn a little yellowish or brown, but they should survive if washed immediately for the most part.
It can take time before the damaged plants produce normal shoots again.
If your flowers are small enough and you think they caught a good dose of the fertilizer, you could dig them up, wash the affected soil from their roots and replant them in a different location.
Can Plants Recover From Fertilizer Burn?
Plants and flowers can recover from fertilizer burns as long as they haven’t received too much of it or are removed from the affected soil, washed, and replanted.
Once the salt is removed from the plant’s soil and the level is back to normal, your plant will begin to take up water and nutrients, grow new roots, and repair the damage that was caused.
As long as you’re careful, there’s no reason why you can’t fertilize your lawn while keeping all your flowers safe.
And if you do get a little fertilizer on your flowers, scoop out as much as you can, cut away damaged shoots, feed, add mulch and water loads to wash away the salts.
If you think the soil has been badly affected, dig up your flowers, wash the contaminated soil from their roots and plant them in another spot.