Early Spring Lawn Care for a Happy, Healthy Lawn

Homegrown Horticulture

00:00 Intro

00:53 Why do some lawns green up before others

02:20 Should I apply lawn pre-emergent

06:00 How to control existing lawn weeds

09:25 Should I aerate my lawn

11:48 Reseeding my lawn

13:59 When and how often to fertilize

Lawn Fertilizers:https://extension.usu.edu/yardandgarden/research/lawn-fertilizers-for-cool-season-turf

Preparing soil for new grass seed: https://extension.usu.edu/yardandgarden/research/preparing-soil-for-turfgrass-establishment-northern-utah

USU Extension Lawn Care Calendar: https://extension.usu.edu/yardandgarden/research/northern-utah-turfgrass-management-calendar

Hello and welcome back to the Homegrown Horticulture podcast. My name is Taun Beddes, a horticulturist with Utah State University Extension based in Orem, Utah. On today's episode we're going to be talking about all things Lawns. I've been getting a lot of questions on (things such as) when should I fertilize, should I use pre-emergent, and because of the sheer number of lawn questions, that's this week's topic.

The Homegrown Horticulture podcast offers detailed gardening information for the Intermountain West, an area of the United States oftentimes neglected or forgotten about by national Horticultural companies. Where recommendations about our climate and our soils made by national gardening companies just aren't valid. And so we need a podcast source of information detailing how to garden in the Intermountain West.

Our first question comes from a gentleman named Chad. He asks why do some green up before others? The reason some Lawns green up before others is because of when they were fertilized. Utah State University recommends fertilizing in late fall. For the Wasatch Front (and other areas with a similar climate) that would be late October into early November. A lot of nitrogen from fertilizer is stored in the roots of the grass before it goes dormant for the winter, and lawns can utilize this nitrogen in early spring. And so you will often see a lawn that was fertilized in late fall green up two to three weeks earlier than a lawn that was not.

Some other factors also play into this. Some species of Turfgrass will green up before others. If you have a Kentucky Bluegrass lawn, these will generally green up a week or so later than if you have a turf type tall Fescue lawn or a perennial ryegrass lawn. These two kinds of lawns are far less common but, you sometimes do see them. Another thing that will cause at least some areas of the lawn to green up before others is the amount of heat that the lawn is exposed to. In the spring, you will often see your lawn greening up long sidewalks, along the driveway, and on the south side of your home before other areas. This is totally normal, and within a few weeks, the lawn should be evenly green.

Alright, the next question is from Jill. she asks, “When should I apply pre-emergent to my lawn.” Before I answer this question, I should offer some explanation, Pre-emergent is a general term for a type of herbicide that will control newly germinating seeds. It doesn't do anything against seeds until they start to germinate. It also cannot discriminate between weed seeds and desirable seeds, and so you really do need to be careful with how you apply pre-emergent in your yard and garden.

And so my first question is why are you using pre-emergent? It's not a bad thing, and they can be a powerful tool at getting the lawn into shape. But the ultimate goal should be not to use pre-emergent (for an extended number of years), and you should use proper management techniques as far as your lawn goes, to make sure that the lawn stays healthy. A healthy and properly maintained lawn does not allow a lot of weeds to invade or germinate. So when you're applying a pre-emergent, you actually need to know what weed you're going after.

On the Wasatch Front the major three weeds that folks use pre-emergent for include spurge, black medic, and crabgrass. It is important to know how to differentiate between these weeds, because a pre-emergent that you would use for crabgrass may not be as effective as one that you would use for spurge.

So if you hire a lawn care professional, the type of pre-emergent they're generally applying goes after crabgrass and other annual weedy grass is quite well but, if you're having problems with spurge or black medic, or other broadleaf weeds, then the particular pre-emergent (products) for Crabgrass maybe less effective. And you would need to veer toward one meant for broadleaf weeds.

Three types of pre-emergent weed control that lawn professionals generally use include Pre-M Dimension, and Barricade. These are all very effective against crabgrass and other annual weedy grasses. They can offer effective control for a number of broadleaf weeds, but you would need to check the label or have your lawn care company look at the label to see if they actually control the weed that you have in your lawn.

If you are applying on your own, all of these products are available from the local garden centers, farm stores and box stores. Also if you have a lot of broadleaf weeds that you're trying to control, you need to know what they (the weeds) are. There are some options for you that are more specific for broadleaf weed problems. One of them is a product called isoxaben. It has been sold in the past as Gallery or Galleria. Right now it is currently available for homeowners from Bioadvance (the company formerly known as Bayer), and the product is called Bioadvance Broadleaf Weed Control for Lawns. I'm not giving a specific endorsement of this, but it's the only homeowner type of product I know of that has isoxaben that's widely available.

There is also an organic pre-emergent that is made from corn gluten meal. Corn gluten meal is oftentimes also used as a fertilizer. So you get a double benefit. I know people that really like it, but I've talked to others that say that it's not really effective. I think it is in some situations it can be. But if you're trying to stay organic, it may be worth a shot.

The next question comes from Jack. He asks, “how do I control weeds in my lawn.” I'm assuming that he's talking about existing weeds. I do want to refer back to the other question on pre-emergent. We state that keeping a healthy lawn is so important. Mowing at 2 and 1/2 to 3 inches, and when you mow don't cut more than a third of the total grass blade off. Fertilizing on an as-needed basis instead of a set calendar (package) that you got from the store, watering a couple of times a week so that water penetrates 6 inches to a foot into the soil is also imperative because that encourages stronger roots that are better able to crowd out weeds.

Oftentimes weedy plants are more common in certain parts of the yard than others. And you need to do some investigation as to why. Things like crabgrass and spurge often grow in compacted soil or areas where it is a little bit drier than the rest of the lawn. And so figuring out why a particular weed is growing in an area of your yard is actually going to be much more important than just spraying those weeds out with a chemical. Because when you know what the problem is, you can begin to remedy it, and this allows the lawn to thicken up. As the lawn thickens up, it will crowd weeds out or make it easier for you to control them.

So let's focus a little bit further. Let's say that you figured out why that weed is there, and you began to remedy the problem. If you choose to use them, herbicides can be a useful tool. And so there are many herbicides out on the market. They are referred to as weed and feeds or dandy-lion killers or broadleaf weed killers. They actually do a pretty good job of controlling most broadly weeds.

And now if you have weedy grasses in your lawn, that's a different problem. There aren't really any sprays available to homeowners that will eliminate a weedy grass out of your lawn because those weedy grasses are so closely related to your lawn grass. Pretty much, spray will kill both (the lawn and weedy grass).

If you cannot identify grassy weeds but you can find a seed head, you can oftentimes get online and identify weedy grasses according to their seed head or send pictures to your local extension office. They’re usually pretty good about knowing what it is. There are many many weedy grasses, and knowing what they are and knowing their life cycle is important to actually controlling them.

One of the most common is pasture type fescue. This is a broadleaf grass that grows in a circle, and it'll expand about 6 inches to a foot every year. This is one that the only control for it is to either smother it and leave it smothered for a couple of weeks. The other is to spray it out. You want to kill it first before you dig it, because if you leave roots in there, it'll just come back. I bring this particular grass up because that just killing the weedy grass out of your lawn is oftentimes all you can do, because if there's a lack of sprays that have the ability to pick weedy grasses out of your lawn.

Our next question is from Mary and she asks if she should aerate her lawn.This is actually a very common question that I get. I should first explain what areating is. When you drive around in the spring or sometimes the fall and you see the little plugs all over people's lawns that look like little dog poops, that's aerating.

It's a machine that actually drives a hollow tube into the soil and pulls out a plug anywhere from an inch to 2 inches long. The reason people do this is to open up the soil. I don't really like that term, and what it does is actually allows more oxygen to be able to penetrate into the soil and water to penetrate the soil more easily. This can be important to your lawn. This does not mean that you need to aerate though, because if you have sandy soils, it is rarely needed. And if your lawn is rarely used, it is probably not needed.

It is more (needed) on lawns that receive a lot of foot traffic or lawns grown on clay soil or lawns that have the potential for a lot of soil compaction due to lots of traffic from vehicles or people.

You always want to use hollow core aeration so you're pulling out the plugs. The best time to aerate is in the spring after you've mowed a couple of times or in late summer into fall, because these are the two times of the year that the lawn can recover quite quickly from the aeration.

Another situation where hollow core aeration can be very useful is if you have too much thatch on your lawn. The (thatch exists between) the border between the soil and the actively growing lawn crowns, where the grass blades grow up through. It looks like a layer of dead grass blades, but it's actually not grass blades. They usually decompose where these (in the thatch) are more crowns and roots.

Kentucky Bluegrass is prone to producing a thatch layer, but if there is actually about a half inch or less, that's considered normal and healthy for the lawn. If the thatch layer is greater than half of an inch, then there's something wrong. Excessive thatch can come from over-fertilization, over-watering, compacted soil, and also clay soil. Hollow-core aerating will definitely help reduce the thatch layer, but it's also important to find out why you have excessive thatch.

Our second to last question comes from Angie. She asks, “can I reseed my lawn over the top of my existing grass to thicken my lawn.” The short answer is yes you definitely can, but one of the themes in this episode of the podcast has been why is my lawn not healthy. and why am I needing to fix it. And so if you're going to use grass seed to fix your lawn, you need to know why the grass thinned out in the first place. So if this goes back to proper mowing; goes back to proper watering; improper fertilization.

Another reason the lawn thins out is too much shade. You may be able to temporarily thicken the lawn up with Kentucky Bluegrass seed, but it will eventually thin back out. Shady grass seed mixes are available at manyi garden centers and farm stores. They actually carry what they would call Shady grass mix or something similar, and you can try those. But you may need to turn to a particular kind of grass called red fescue. Red fescue is going to be the most shade tolerant grass that will grow in the Intermountain West. Otherwise, if you have figured out why your lawn thinned out, and it was due to shade, you are absolutely fine to reseed.

Early spring is among the best times of the year to do that because of the cooler temperatures and rain that we regularly get, and if you do need to irrigate, you do so less often because of the cooler weather. Late summer is also an excellent time to reseed because weed seed is less likely to germinate then do to it needing a cold period during the winter to germinate. Also as temperatures cool down, you need to irrigate less often, and there's still plenty of time for the seed to get established before winter.

Aerating before you reseed can help increase germination rates by helping the seed come into better contact with a soil. Additionally, you may cover the area that you reseeded. A quarter of an inch of compost spread over the new seed would help keep moisture in the soil and increase the number of seeds that germinate.

The final question is from Carl. He asks “when should I start fertilizing my lawn.” Utah State University recommends fertilizing your lawn according to how your lawn is used. Additionally, we always recommend composting your grass clippings back onto your lawn. Sometimes in the spring you get too many clippings, and you need to bag them. When you have to bag your clipping then the recommendation is to put them in your garden or flower beds. And use them as mulch to reduce the number of times you need to irrigate and also to help hold weeds down. When you mulch your grass clippings back into your lawn, it actually reduces the number of times you need to fertilize to the point that you can skip one fertilization a year. And so for a little used lawn that pretty much the only time it sees traffic is when it's mowed, fertilizing in April and September at recommended rates on whatever you buy is absolutely fine, and it will keep your lawn green.

If you have a moderately used lawn, then fertilizing three times a year in mid-April to early May, again in early September, and then your final fertilization would be in late October to early November.

For heavily used lawns, and this would include situations where you're having lots of garden parties, or having kids playing on your lawn quite often, I recommend up to four fertilization to your lawn. And in these situations, you can actually just purchase a 4 or 5 step program from a local garden center or box store and follow it. It will help your lawn stay healthy if it is very heavily used.

Thank you so much for listening. I greatly appreciate it. I'll talk to you again next week.

The Homegrown Horticulture podcast is a production of Utah State University Extension. intro and outro music is composed by Savanna Peterson Utah State University Horticulture assistant and talented musician it is used by permission