Posted on

wjens best time to weed feed seed

Lawns: spring and summer care

At this time of year, the lawn is actively growing and how you look after it depends on what you want to achieve. To encourage wildflowers for pollinating insects, it’s time to stop mowing and enjoy the visits to the flowers that appear. To create a short, green sward, however, you’ll need carry out of range of tasks we explain below.

Quick facts

Jump to

Suitable for.

No longer are all lawns green and striped. Over the last few decades, many gardeners have come to love the joys of seeing and supporting the insects and wildlife that visits long grass.

If you’d like to convert your lawn into a wildflower meadow, or even just a small section to help wildlife, we’ve got lots of information to help you:

However, if your preference is still to go for a short lawn of mainly grass (perhaps because you have incorporated many other plants of wildlife benefit in your garden such as those listed in RHS Plants for Pollinators), you’ll have a range of tasks to do in spring and summer.

All lawns need feeding in order to maintain vigour. When feeding, look out for signs of pest or disease and deal with moss if required. These can often be controlled with cultural methods such as raking. Regular maintenance is the best way to approach a lawn, and may avoid the need for renovation later on.

Over winter, the lawn does not grow much, but once the weather warms up in early spring, you can start mowing, and this is also a good time to over-seed any areas damaged over winter.

Lawn care

Below are some of the tasks to undertake over spring and summer if you are trying to grow a short, green sward – a traditional lawn (for details of growing a rich wildlife habitat, such as a mini meadow, see Wildflower Meadow: Maintenance).


Mowing regularly keeps the lawn in good health, detering weeds and encouraging thick grass. See our advice on lawns: mowing for more on the different cutting heights and mowing frequencies recommended in spring and summer.

Managing moss

Moss is a problem in damp, poorly drained lawns. Spring is a good time to remedy moss problems. There are several options for dealing with moss in lawns, see our advice on moss in lawns for further detail.


In mid-spring (often late March to April), use a proprietary spring or summer lawn fertiliser at the manufacturer’s recommended rates. Feeding the lawn will increase vigour and help prevent weeds and moss from establishing. Apply fertilisers when the soil is moist, or when rain is expected. However, it’s important to know that fertilisers use a lot of energy to make, so using the minimum required to keep your lawn in shape is best for the environment.

If grass loses its vigour and freshness between late spring and late summer (often May to August), repeat the application of spring or summer lawn fertiliser or apply 15g per sq m ( ½ oz per sq. yd) sulphate of ammonia mixed with four times its weight dry soil. Mixing with soil ensures even distribution and avoids scorching the grass. Apply this mixture in cool, moist conditions and lightly water it in. As an organic alternative, use chicken manure pellets. Repeat fertiliser application a third time if needed six to eight weeks later.

Do not apply spring or summer lawn fertilisers, chicken manure pellets or sulphate of ammonia after August. They contain too much nitrogen for autumn use, encouraging green leafy growth at the wrong time of year, when it could be damaged by winter cold or pests and disease.


After moss or weeds have been removed, or where grass is growing sparsely, over-seeding may be necessary. Early autumn is the best time for this job, but mid-spring is also suitable.

  • Break up the surface with a fork and rake it to make a reasonably fine surface
  • Sow grass seed at half the recommended rate or, where there are no recommendations, at 10-15g per sq m ( ½ oz per sq yd)
  • Lightly rake to incorporate the seed into the surface
  • Where birds are a problem, net the area
  • If the weather remains dry for two or three days water gently with a sprinkler
  • Grass should sprout seven to 10 days after sowing

In heavily used areas, choose a hardwearing utility mix containing ryegrass. Most lawn grasses do not thrive in shade, so for these areas choose a shade-tolerant mix.


Even if lawns turn brown and dry over summer, they usually recover well when rains return. Watering is usually not necessary over summer. See our advice on lawns: care during drought for more on limiting damage and conserving water in the lawn.

If you do have to water the lawn and maintain a green sward, water when the soil becomes dry, but before the grass turns yellow or brown. If the ground is very hard, aerate it by spiking with a garden fork before watering, to aid water penetration.

Watering once a week to every 10 days is normally sufficient. Ensure that the water reaches a depth of 10cm (4in) after each watering. In the middle of summer 1 sq m (1 sq yd) needs about 20-litres (5 gallons) every seven days.

Looking after new lawns

Lawns from turf should be left completely un-used for their first week. Lawns from seed should be left un-used until their first mowing. Avoid using new lawns heavily in their first season.

Newly laid lawns can be fed like established lawns. They need watering, but should not be over watered, as this may result in shallow rooting and poor establishment.

For advice on aftercare of newly sown lawns, see our advice on lawns from seed.


When over-seeding the lawn, it can be difficult to match the colour of a new seed mix with your existing lawn. In such circumstances it may be necessary to over-seed the whole lawn to achieve uniformity of colour and texture.

Areas of dry shade, such as under trees, become sparse very quickly despite adequate care. Consider over-seeding on an annual basis to maintain a dense sward.

Spring is a good time to repair damage to lawns caused by pests, diseases or mechanical damage.

When to Fertilize the Lawn in Spring

Kelly Burke is a professional turf manager for a manicured corporate campus in New England. He is accredited in organic land care and is a licensed pesticide applicator. He formerly managed the turfgrass as a golf course superintendent and has held several senior management positions at private country clubs overseeing high maintenance lawns.

  • Pin
  • Share
  • Email

The Spruce / Jayme Burrows

Most people apply a dose of lawn fertilizer in the spring, followed by one or two more applications during the growing season. If you are going to fertilize your lawn, do not do it too early in the season. The best time for that first application is late spring, just as the green grass is beginning to grow eagerly. In early spring, the grass is putting energy into root development. If you apply fertilizer too early, it will divert the plant’s energy into leaf development too soon.

A healthy lawn will be a relatively light shade of bright green. A lawn that is a deep, almost blackish green, has been very heavily fertilized. The dark green color comes from a lot of nitrogen-based fertilizer used on the lawn.

Debating the Use of Fertilizer on the Lawn

Whether or not you should use fertilizer on a lawn depends on where you stand on organic or low impact-to-chemical gardening practices. Organic gardeners avoid the use of any chemical products as lawn fertilizers. The main concern is the fertilizer run-off can enter the local water supply. There is good evidence that shows phosphorus and nitrogen from lawn and agricultural fertilizers are contaminating streams, rivers, and groundwater supplies, creating a pressing environmental problem.

Organic Lawn Fertilization

There are a few organic methods of feeding a lawn safely. You can choose to use a mulching mower that chops up grass into fine particles that then break down on the lawn. Horticultural experts say that throughout the season, this technique provides a lawn with as much nitrogen as one complete application of lawn fertilizer. You can also use organic fertilizers made from natural materials instead of refined chemicals. Organic-labeled fertilizers will indeed feed your lawn, though they are usually less saturated with the essential nutrients (nitrogen, phosphorus, and potassium) than the industrially refined fertilizers.

Non-organic Lawn Fertilization

Traditional chemical lawn fertilizer remains the most popular choice and is widely available at hardware stores, big-box home improvement centers, and garden shops. These fertilizers come in many varieties. Some fertilizers match the season, such as early-season fertilizers, mid-summer fertilizers, and late-season “turf-builder” mixes. Other fertilizers are better suited for flowers or vegetables. Another category contains herbicides, which feeds the grass, kills weeds, and prevents weed growth.

Pre-emergent herbicides are a combination of fertilizer and crabgrass control herbicide applied in the early spring. This combination product does not have a full feeding of fertilizer. This small dose of fertilizer slightly boosts grass growth and keeps it alive, while the herbicide in the product restricts crabgrass seedling development.

Apply Fertilizer Prudently

Across the board, most fertilizer manufacturers are overzealous about their recommended dose and feeding schedule (the more you use, the more you have to buy!). Start light with half the recommended amount and rate of fertilizer. You can reapply if you don’t like the results. Over a season or two, you’ll get a clear sense of how much it takes to get a healthy lawn.

Fertilizer Application Timing

Homeowners who prefer organic fertilizing methods might do a single "turf-builder" application in the early fall to build root systems. In the spring and summer, most may omit all fertilizers and rely on the nitrogen from mulched grass clippings to feed their lawn.

Homeowners using traditional fertilizer might want to apply two or three light applications per growing year—one in the spring, one at midsummer in regions where it is necessary, and one "turf-builder" application in the early fall.

The actual timing depends on your region and the type of turf grasses you have. For information on the best recommendations for your area, contact an expert at a local garden center or reach out to the nearest cooperative extension office.

Once you have figured out the best time, try to plan the fertilizer application with a short period of rainfall. If not, when you apply the fertilizer, you will need to supply your lawn with at least a quarter-inch of water. However, do not apply fertilizer before a massive storm. A rainstorm increases the risk of fertilizer nutrients flowing into storm ​drains and streams.

When to Apply Lawn Fertilizer in Spring

If you fertilized your lawn the previous fall, especially late in the season, then the slow-release function of that fertilizer will help grass growth in the spring. Fertilizer manufacturers or lawn care companies may tell you to fertilize your lawn in early spring, but instead, consider the guidance by turf specialists and agronomists (soil experts) who say to hold off.  

When cool-season grasses “wake up” in the spring, they enter a natural growth cycle when the root system begins growing and building carbohydrate (energy) reserves. Wait until the late spring (late May or early June) just before the heat of summer begins and after the grass is thriving before you fertilize the lawn.

Feeding your lawn at this point prepares the grass for summer. During the hot summer months, the grass will begin to slow down carbohydrate production and begin to utilize the reserves. Adequately feeding 3/4 to 1 pound of slow-release nitrogen will allow the grass to rebuild its energy (carbohydrate) reserves and ward off the stresses of summer, such as drought, heat, traffic, disease, and insects. A polymer-coated slow-release fertilizer can feed the grass for up to 12 weeks.

Feeding the Lawn in the Summer and Fall

Warm-season grasses thrive in the heat of the summer and can be fertilized throughout the growing season. However, cool-season grasses are in a survival mode during the heat of the summer. Refrain from applying fertilizer to a lawn in mid- or late-summer if you live in a climate where cool-season grasses are in your lawn seed mix. A cool-season lawn should need nothing other than water and pest management until September.

Most lawn experts recommend a mild dose of a “turf-builder” fertilizer formulation in the early- to mid-fall, while the turf still has several weeks of active growth before dormancy.   This application will help build robust root systems going into winter and restart the growing cycle in the spring. You are not looking to return your lawn to the green of summer. Heading into winter, you can expect a natural slowdown of your lawn’s growth and the loss of its green luster.

The Quick and Easy Guide to Fertilizing Your Lawn

Fertilizer is a key ingredient in growing and maintaining a green, healthy lawn. Unfortunately most homeowners don’t bother fertilizing because they simply don’t know which products to use, or how and when to apply them. And complicating the issue is that if lawn fertilizer isn’t applied correctly, it can actually do more harm than good.

So, to help advise us on the proper way to fertilizer a lawn, we contacted Jeff Turnbull, president of LCS Lawn Service in the Twin Cities. Here are his nine simple-to-follow rules for fertilizing lawns.


The very best time to fertilize your lawn is in the spring, when the soil temperature—not the air temperature—reaches 55º Fahrenheit. You’ll know when the soil warms up to 55º because the lilacs will begin to blossom and the grass will start growing.

Or, buy a soil thermometer and check the temperature at any time. In most parts of the country that means the first application of lawn fertilizer should take place by about mid-April. So, if you haven’t started yet, mark that date.

When shopping for fertilizer, you’ll find three numbers printed on the label. These numbers represent the percentage of nitrogen, phosphate, and potassium, respectively, which are the primary nutrients needed to feed your lawn. So, a 20-5-10 bag will have 20 percent nitrogen, 5 percent phosphate, and 10 percent potassium. The rest of the bag usually contains filler material that helps ensure an even application of the fertilizer. By the way, a 20-5-10 lawn fertilizer is a good basic mix to use in spring.

Slow-release lawn fertilizers break down their nutrients over a longer period of time, so you can wait longer between applications. “With slow-release fertilizers, you can feed your lawn every six to eight weeks, depending on your watering schedule, instead of every four weeks,” Turnbull says. That saves you both time and money.

He recommends a slow-release that contains nitrogen, but not too much. “The most nitrogen you need on a lawn is one-tenth of a pound per week. The grass can’t get any greener than that. If you use more, you’re only going to make the grass grow faster so you have to mow more often,” Turnbull explains. “The secret is to get it as green as possible without growing it fast.

“Turnbull recommends giving your lawn between two and three pounds of nitrogen over the entire growing season. “If you go with 25-0-4 fertilizer, that gives you one pound of nitrogen. So, over four weeks, that’s a quarter pound of nitrogen per week, which is way too much,” Turnbull says. “At that point, you’re baling hay instead of mowing a lawn.”

When professional landscapers apply fertilizer, they often drive up in a tanker truck and spray your entire lawn in a remarkably short amount of time. But pros do this every day, so they know how to factor in for the wind and make sure the yard gets even coverage. And they have the proper equipment to get the job done right. Homeowners, on the other hand, should use granules, which are super simple to apply using a spreader (see tip No. 7).

“Granular fertilizer is very easy to apply accurately,” Turnbull says. “When you’re spraying fertilizer, it’s tough for a homeowner to get a consistent, even application across the entire lawn.”

As mentioned earlier, Turnbull recommends giving your lawn its first feeding of fertilizer in the spring—mid- to late-April in most regions—once the soil temperature reaches 55º Fahrenheit. Your local university extension office can give you the soil temperature in your neighborhood, but again, you can use a soil thermometer or wait until the lilacs blossom, as an indicator that the soil is 55º.

Now, the second feeding should happen about four weeks after the first application, around mid-May or so. Then fertilize every six to eight weeks after that straight through to October. For the third feeding, use an organic material, such as manure, instead of a traditional lawn fertilizer.

And remember that fall feeding is critical, too. “Grass continues to grow throughout the fall. The roots are going down into the soil and they need fertilizer,” Turnbull says. “In fact, this is the most important application of fertilizer for the whole year.” And use a fall fertilizer that’s slightly higher in phosphorous and potassium, which will promote better root growth.

Fall Lawn Food BUY NOW

Contrary to what some people think, the more you water your lawn, the more fertilizer it needs. “With more water, there is more growth, so you need more fertilizer,” Turnbull says. “As the grass grows, it uses more nutrients.” If you have an automatic sprinkler system, you should fertilize your lawn about every six weeks. Without a sprinkler system, you can wait an additional two weeks between feedings.

Also, be sure to carefully read the fertilizer label to learn whether you should water the lawn before or after applying the fertilizer. Granulated fertilizers need moisture to break down, and some fertilizers require you to soak the lawn prior to application.

When you’re ready to pour fertilizer into the spreader, park it on the driveway or patio. If you can’t, at least put a tarp under it. This will keep any spilled granules from accumulating in one spot on the lawn, where they can burn and kill the grass.”

And make sure your hopper is shut before filling up the spreader,” Turnbull says. “That’s lesson number one that everyone forgets at least once.” (If the hopper is left open, the fertilizer will pour right through onto the ground.)

A broadcast spreader is a better choice than a drop spreader for homeowners. Broadcast spreaders are easier to use, and since they disperse fertilizer a wider distance, there’s less chance you’ll end up with stripes in your yard caused by not properly overlapping the rows. Plus, broadcast spreaders are pretty affordable, starting at about $30.To fertilize small yards, use a handheld broadcast spreader, which has a hand crank. You can buy one for as little as $15. These compact spreaders are particularly useful for fertilizing narrow side yards, and grassy areas along fence lines, around trees, and behind garages and sheds.

Regardless of what type of spreader you use, be sure to walk at a consistent, steady pace as you apply the fertilizer. Failing to do so will cause the fertilizer to be spread too thin in some spots and too thick in others.

Every fertilizer label will list the application rate, but Turnbull recommends that you don’t follow it. “Start out at half of what’s recommended on the bag,” he says. “One of the biggest mistakes homeowners make is applying fertilizer with the spreader wide open.” He recommends spreading the fertilizer at half or slightly less than half the manufacturer’s recommended rate.

Start by applying fertilizer around the perimeter of the yard first, and then fill in the middle, working in one direction. Then, spread it again, moving in a perpendicular direction. This crisscrossing pattern ensures much better coverage and helps prevent over-applying the fertilizer. “When it comes to spreading fertilizer,” Turnbull says, “too little is better than too much. I always recommend erring on the side of too little.” A heavy dose of fertilizer isn’t only a waste of money, but it can burn and kill the grass.

Since you’re applying the fertilizer at half the recommended rate, it won’t spread out very far, so you don’t need to estimate how much spacing to keep between rows. “Go from tire-track to tire-track on the spreader,” Turnbull says. “This will guarantee good, even coverage.”

And be sure to check the weather forecast prior to fertilizing. If you apply the fertilizer right before a downpour, much of the fertilizer will be washed away.

No matter how careful you are the spreader will occasionally throw fertilizer onto your driveway, sidewalk, or patio. If that happens, sweep it up rather than letting the rain wash it away.

“If you don’t sweep up and collect the excess fertilizer, it just adds extra pollution,” Turnbull says. “It gets washed away into storm drains and then ends up in the rivers, streams, and lakes. Sweeping up the fertilizer is good for the environment.”

Finally once you’ve finished fertilizing your lawn, pour any leftover fertilizer out of the spreader and back into its original bag. Tightly seal the bag and store it away in a cool, dry place, well away from any children and pets.