At Master Lawn, we typically say to wait 24 hours before watering your lawn after fertilizing. But it is important to make sure that it does receive a good watering session soon after that 24 hour waiting period. Watering helps the fertilizer to activate and to break down and begin feeding nutrients to the lawn.
A granular fertilizer application can be watered in immediately after application. In fact, the product could even be applied in the rain if it were functionally possible!
If your lawn gets liquid fertilizer, wait until it dries before watering, about 2-4 hours. If it's granular fertilizer, water right away. One exception: if you also got spot weed treatments at the same time, wait for that to dry before watering, or the water will wash off the weed killer before it can work.
Granular Fertilizers: These can often be applied directly to the soil without mixing with water. However, watering the area after application can help dissolve the granules and promote nutrient uptake by plants.
Most granular fertilizers dissolve within 24 to 48 hours, though the formula and brand may impact the overall dissolve time. Read through the packaging to get a better idea of how you should apply the fertilizer and how long you should wait to mow to ensure it dissolves properly.
Heavy Rain Immediately After Fertilization: Heavy rain, on the other hand, can wash away the fertilizer, preventing your grass from benefiting from the nutrients. In some cases, the fertilizer may disperse unevenly across your lawn, leading to irregular growth or even scorching.
Instead, you need to wait for a couple of hours (in the case of liquid fertilizer) or between 24 and 48 hours (in the case of granular fertilizer) before you can mow the lawn.
Watering helps the fertilizer to activate and to break down and begin feeding nutrients to the lawn. The key nutrients that a lawn needs are Nitrogen (N), Phosphorous (P), and Potassium (K), all of which are found in fertilizer, and each of which has a different function.
Granular fertilizers are excellent for applying to wet grass, as they adhere better and dissolve gradually, providing a steady supply of nutrients to your lawn's root system. Opt for slow-release formulations to sustain nourishment over an extended period, especially during periods of drought or excessive heat.
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”.
It's generally recommended to wait about 24-72 hours after a fertilizer application before letting your kids go back onto the grass and to also ensure your lawn is watered well before the kids go back to playing in the grass.
As a side note, never apply fertilizer when extended drought conditions are expected. It won't do your plants any good; you'll waste money on fertilizer because it will eventually become inactive, and whatever is left will simply wash away in the next big rain.
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.
Fertilizer doesn't expire, but we recommend keeping it dry and in an airtight container, and using it up within a year to get the best results. The longer the fertilizer sits unused, the more likely it is to become damp and clumpy, which could make it hard to spread.
To water well, timing is everything. Water in the early morning – between 6 a.m. and 10 a.m. Midday watering leads to wasteful evaporation, while nighttime watering causes droplets to cling to grass overnight, increasing the chance of lawn diseases.
If you're asking does lawn fertilizer go bad in granular form, the answer is no, provided it's stored properly. Granular fertilizers can last indefinitely as long as they are kept dry and away from moisture. However, if moisture gets in, it can cause clumping, which affects its effectiveness.
Key Takeaway – Granular fertilizers are better for sustaining the long-term health of your lawn, but each granule has a unique nutritional makeup, which may result in an uneven lawn.
Ideally, you should apply a fertilizer treatment to a dry lawn when there is no rain forecasted for the next couple of days.
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.
Generally, granular fertilizers are designed to dissolve gradually 24-48 hours, providing a slow-release of nutrients to the plants.
Magic Carpet is a strong slow-release fertilizer. It is not diluted, but it is a slow-release nature prevents it from burning your lawn. The strong commercial grade wax coating (XCU= 65%) on the granules allows it to break down slowly over time, usually taking 6-8 weeks to completely dissolve.
If you're uncertain what fertilizer was used or want to play it safe, waiting 24 hours is your best bet to protect your pup. However, if your dog starts to show signs of illness, such as dizziness or vomiting, even if it's been more than 24 hours after fertilization, contact your local veterinarian as soon as possible.
Is every two weeks too often to fertilize my lawn? While you could fertilize this often, it will lead to over-fertilization in most cases, so we don't recommend it. You could put a small amount of fertilizer down more often, but there's no benefit to doing this, and it just causes unnecessary work.
Before applying fertilizer to the lawn, it's important to mow it first to clear away any thatch. This allows the fertilizer to make better contact with the soil. When the spring fertilizer makes better contact with the soil, it will be absorbed more easily by the roots of your grass.