Some shun weed and feed products, for a variety of reasons. Find out why, as well as whether there may be some instances where they make sense. Weed and feed lawn products combine a lawn fertilizer with a weed killer and/or weed preventer in one product. Different turfs call for different types of products, and application timing is critical. Check out these tips for before and after application for lawn weed and feed fertilizer. Now that the weather is warming up, outdoor activities are gearing up, and you’re finally looking at your lawn. Homeowners may be tempted to run to their local lawn and garden store to pick up a bag of Weed-n-Feed. Many “experts” will tell you that this is the best way for homeowners to control weeds and fertilize for “season long control”.
Should You Use Weed and Feed? Weed and Feed 101
Kathleen Miller is a highly-regarded Master Gardener and Horticulturist who shares her knowledge of sustainable living, organic gardening, farming, and landscape design. She founded Gaia’s Farm and Gardens, a working sustainable permaculture farm, and writes for Gaia Grows, a local newspaper column. She has over 30 years of experience in gardening and sustainable farming.
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“Weed and feed” is a catchy name for products promising something bound to catch the attention of any busy homeowner looking to save time and energy through low-maintenance landscaping. Who wouldn’t want to satisfy two landscaping needs in one operation? As straightforward as that sounds, whether people should use weed and feed can be a question harder to answer than you initially think. We’ll approach the question by discussing the products’ ingredients, effectiveness, and downsides. In case you conclude, from this information, that you’d prefer to use alternatives, you’ll learn about those, too.
What Is Weed and Feed?
“Weed and feed” is an umbrella term for certain 2-in-1 lawn products. They contain both chemical herbicide and chemical fertilizer, so you can kill weeds and feed your grass simultaneously.
What’s In Weed and Feed?
Because “weed and feed” is an umbrella term, there’s no one set list of ingredients for it. Not only is it sold in different forms (granules vs liquid), but it can also serve different purposes. If you’re trying to thwart weeds before they emerge, then you need a weed and feed that contains a pre-emergent herbicide. But if you need to kill weeds after the fact, the product to use is one with a post-emergent herbicide. The “feed” ingredients are not always exactly the same either. For example, the NPK ratio may vary (some mixes leave out phosphorous altogether).
But the typical bag of weed and feed with post-emergent herbicide contains:
- 2, 4-D, dicamba, MCPP (herbicides)
- Nitrogen, phosphorous, and potassium (fertilizer)
A typical bag of weed and feed with pre-emergent herbicide may contain, among other ingredients:
- Dithiopyr (herbicide; often sold as “Dimension”)
- Nitrogen, phosphorous, and potassium (fertilizer)
What Is an Herbicide vs. a Pesticide?
You’ll sometimes see weed and feed referred to as containing pesticide and fertilizer, which is confusing for beginners. “Pesticide” is a more general term than “herbicide.” A pesticide is a product that kills some type of pest. While “pest” may evoke images of mice or cutworms, weeds are also considered pests. An herbicide is a type of pesticide that specifically kills plant pests (weeds).
Does Weed and Feed Work?
Weed and feed can work, but only if you take the trouble to become informed about lawn care. These are not products suited to those unwilling to do any homework.
Timing is of the essence. Weed and feed is typically applied in spring, but timing here is complicated by the fact that you need to time two different things: weeding and feeding. Let’s assume you’re applying weed and feed with post-emergent herbicide: If you apply it too early, you may kill only a small percentage of the weeds. The weeds that haven’t yet emerged will avoid the post-emergent. But, if you apply it too late, your grass won’t receive the feed it needs to get off to a good start in spring.
Consequently, you’ll need to strike a balance. Your best bet is to apply weed and feed approximately when you notice the grass needs its first mowing of the season.
In their criticisms of weed and feed, detractors go well beyond pointing out the difficulty of striking this balance. They argue that, even if you arrive at just the right balance, an application made so early in the year (to satisfy the needs of your grass) generally doesn’t coincide with the ideal timing for killing weeds, most of which emerge later. Consequently, a potentially harmful chemical is being applied to your lawn that does relatively little good. While this is true, the argument is unlikely to persuade a homeowner whose lawn has been overrun by dandelions and who desperately wants to get rid of them: Dandelions are an example of a weed that emerges early in the year, so a post-emergent is effective against them.
Moreover, the argument limits itself to the issue of the effectiveness of post-emergent herbicides and fails to consider the utility of pre-emergent herbicides. Crabgrass is one of the most pernicious weeds and is best controlled with pre-emergent herbicides. Weed and feed designed to suppress crabgrass seed germination in spring could be the right answer for you if you’ve been fighting a losing battle with crabgrass.
Don’t assume the product you’re looking for will have “weed and feed” in its name. One weed and feed that may help you in your battle with crabgrass announces itself as “Crabgrass Pre-emergent Plus Fertilizer.”
How Weed and Feed Can Harm Your Lawn
But such a product will never be the right answer if you’re an organic gardener. Environmentalists are generally opposed to the use of chemicals on the lawn due to the potential harm they cause the environment.
To illustrate how controversial weed and feed is, we need only turn to Canada. That country banned it in 2010 (although you could still buy the herbicide or the fertilizer separately). The ban was meant to target cosmetic use of weed and feed (on residential, commercial, and recreational turf, such as golf courses), carving out an exception for agricultural use.
Continuous use of weed and feed may even negatively impact long-term lawn health. Weed and feed harms soil micro-organisms that are beneficial to grass.
Alternatives to Use
First of all, always ask yourself the question, Do I really need to apply an herbicide? When you notice the grass needs its first mowing of the spring, look around and see how many weeds are present. If you have done a good job in the past of keeping your lawn weed-free, you may not need to use a post-emergent herbicide. As for pre-emergent herbicides, an organic choice is corn gluten meal, which also contains some nitrogen (natural fertilizer), making it something of an “organic weed and feed.”
More generally, simply realize that it may be better to apply herbicides and fertilizers separately, rather than together. It may take more time, but they may work better when used separately, since you’ll be applying them when they’re most effective. This way, you can also limit the adverse impact of potentially harmful chemicals by spot-treating weeds with post-emergent herbicide when and where they appear, thereby reducing the total amount of herbicide released.
It’s easier to go totally organic on a small lawn than on a larger lawn. When the surface to be maintained is minimal, it becomes more feasible to weed your lawn through hand-pulling and to feed it with compost.
Weed And Feed Lawns: Where To Begin
Weed & Feed products combine a lawn fertilizer with a weed killer and/or weed preventer in one product. One application does double duty, treating random weeds spread across an entire lawn while also feeding and greening grass. Weed & Feeds come in two basic formulations, granules and liquids. But before you make an application, here are some things you need to know about weed & feed products.
Weed & Feed Starts With Weeding…
The “weed” half of “weed & feed” contains some mix of herbicides to kill lawn weeds. Almost all products contain a post-emergent herbicide, but some also combine a pre-emergent herbicide designed to prevent new weeds from sprouting.
Post-Emergent herbicides kill existing lawn weeds like Dandelion, Clover and many other common weeds. The complete list of weeds can be found on your product’s label. These post-emergents are always selective herbicides, so they will not harm existing grass when applied as directed. New innovations, like BioAdvanced 5-in-1 Weed & Feed, also kill grassy weeds like Crabgrass, eliminating the need for multiple applications of additional herbicides to achieve control.
Pre-Emergent herbicides are meant to keep new weeds from germinating and growing. Timing is the key, apply too early and the preventer can become ineffective while weeds are still dormant. Apply too late and seeds may have already germinated. You’re probably most familiar with Crabgrass preventers that are applied in early spring.
…And Ends With Feeding
The “feed” half of “weed & feed” is all about fertilizer. Most fertilizers are a mix of nitrogen and other macro-nutrients, and sometimes micro-nutrients, in varying amounts. Nitrogen (N) is the most important element in lawn fertilizers and comes in two basic forms – fast-release and slow-release. Most lawn fertilizers include a mix of fast-release and slow-release forms to provide quick green-up and sustained growth.
Fast-Release Nitrogen (often referred to as water-soluble nitrogen or WSN) such as urea and ammonium sulfate, is readily available and absorbed quickly by the grass, resulting in fast green-up. Unfortunately, it can also can burn your lawn if applied improperly, and can leach through the lawns root zone or run off the lawn in heavy rain, causing pollution.
Slow-Release Nitrogen (often referred to as WIN or water-insoluble nitrogen), such as sulfur-coated urea, methylene urea and animal manures, are released more slowly to the grass and provide more sustained, even growth – up to 3 months for methylene urea.
Before You Begin, Know Your Lawn Type
Before applying any type of weed & feed or fertilizer product, you need to identify your type of grass. Some fertilizers can be applied to all lawn types, but most weed & feed products are specifically labeled for certain types of grasses. Apply the wrong product to the wrong type of grass and you can damage your lawn. Use caution and read the label. If you’re still unsure, use the toll-free number found on the label to contact the manufacturer.
When To Apply
Weed & Feed products are most effective when weeds are small and actively-growing, namely spring and fall.
In spring, wait to apply until you’ve mowed your lawn two times before applying to be sure it has emerged from dormancy.
In fall, be sure to check the with local Cooperative Extension System office for historical frost dates in your area. Many Weed & Feed labels will recommend application timing based on that date.
Most weed & feed products will have temperature restrictions as well, be sure to check the label. Do not apply to water-saturated soils, lawns under stress from drought, disease or prone to injury.
How To Apply
For liquid weed & feed products, be sure to use one of the sprayer types recommended on the label and follow label instructions for mixing and spraying.
For granule weed & feeds, use a rotary or drop-type spreader. Drop spreaders apply fertilizer very precisely in a narrow band directly below the spreader, while a rotary spreader broadcasts over a wider area. The application pattern is very important. Be sure to follow label instructions.
Both types of spreaders have adjustable application settings. How much fertilizer is applied varies according to the settings on the type and model of spreader you use. Read the spreader manufacturer’s instructions before fertilizing to help you calibrate your equipment to ensure proper application rates. You’ll find the proper setting for your type of spreader on the specific fertilizer label. If not, there should be a toll-free phone number to call. Do not use the spreader until you are sure it is set properly. You can learn more about calibrating your spreader and spreader settings. Be sure to read always and follow label instructions.
Other Things You Should Know
Mowing – For best results, mow your lawn 1-2 days prior to application. Clippings from your next three mowings should be left on the lawn. Be sure not to use these clippings as mulch or compost around flowers, ornamentals, trees or in vegetable gardens.
Do Not Rake – Heavy raking will disturb the weed preventative barrier and reduce the effectiveness of this product.
Watering – Many weed & feed products instruct you to wait 24 hours before watering in. Be sure to consult your specific label.
Feeding New Lawns – Most new lawns don’t need to be fertilized until 6-8 weeks after planting. However, that can vary depending on how the soil was prepared before planting and the type of fertilizer used. Consult your local Cooperative Extension System office or nursery for recommendations on fertilizing new lawns.
8 Reasons Weed-‘N’-Feed May Not Be Right for You
Now that the weather is warming up, outdoor activities are gearing up, and you’re finally looking at your lawn. Homeowners may be tempted to run to their local lawn and garden store to pick up a bag of Weed-n-Feed. Many “experts” will tell you that this is the best way for homeowners to control weeds and fertilize for “season long control”.
The reality is, you will pay top dollar for a subpar product. Once you factor in the product costs and your time, it will be less expensive in the long run to hire a professional that is certified in lawn weed control and fertilization. Personal Lawn Care, Inc. provides three weed control and three fertilization applications with free touch-ups throughout the season. Our program provides true “Weed-n-Feed” for your lawn.
Here are 8 reasons you shouldn’t use Weed-n-Feed
1 Wrong Amount: One of the reasons most homeowner are unhappy with their Weed-n-Feed application is due to an improper rate of application. If you apply the product too thin, the weeds will be able to break through; too heavy and you risk burning your lawn or stressing it out. Sometimes the product itself is poorly formulated or simply too strong for your lawn.
2. Bad Timing: There is a small window of time (usually 6-12 weeks) where you can control spring weeds. If you have a hard time fitting lawn care into your schedule (like most homeowners) and it creeps into May or June before you apply Weed-n-Feed products, they will at the least be ineffective and at most damage your lawn. Unfortunately your local lawn and garden center will sell Weed-n-Feed products well into the summer.
3. You don’t water it in: There are two irrigation aspects that must be met when using Weed-n-Feed products. First, the leaves of the weeds must be wet before the product is applied. To take care of the weeds that have already germinated, the product must stick to the leaves. Then, about 24hr later it must be watered in. The product has to soak into the soil to work on germinating weeds. Products that your local lawn professional apply soaks deeper into the soil preventing germination. Basically knocking out those weeds before they have a chance.
4. The product doesn’t cover all weeds: Even though the Weed-n-Feed you get at your local lawn and garden center says it covers a broad spectrum of weeds, they may be overselling their product. Most of their products are sold nationwide. It is impossible for one product to cover every weed eventuality. Personal Lawn Care tailors the products applied to meet your specific weed control needs. This provides targeted control for even the hardiest of weeds.
5. Won’t prevent weeds in the future: Just because your Weed-n-Feed takes care of your dandelions now, it may not take care of the crabgrass that springs up a week later. There may be products that last longer, but for better control, contact your local lawn care professional.
6. You don’t know how safe the product is: There is a lot of debate about products used for weed control. The Weed-n-Feed products available may contain any number of chemicals. Just because the Department of Agriculture approves a product to be used on your lawn, doesn’t mean that it is safe for you, your children, or your pets. Over the past 30 years, Cullen Beard, owner of Personal Lawn Care, has taken great care in choosing which products are applied to your lawn. His background as a science and chemistry teacher makes him qualified to research the products in depth. “If I wouldn’t use the products on my own yard, around my own children, then I won’t use it on yours”.
7. Too much Nitrogen: The “feed” part of Weed-n-Feed products is usually a high nitrogen fertilizer. High nitrogen fertilizers should only be used during the summer when the lawn has come completely out of dormancy. Providing your lawn with too much nitrogen too early in the season will weaken root growth thereby making it more susceptible to drought or other stresses. Cullen recommends a high phosphorous fertilizer in the spring followed by a high nitrogen fertilizer during the summer.
8. Can interfere with seeding: If you are planning to seed your lawn, Weed-n-Feed will stop you in your tracks. Because Weed-n-Feed kills the weeds as they are germinating, it will also kill your delicate grass shoots. If you are planning on seeding, you should refrain from using any pre-emergent weed control until the new grass is well established.