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A person sprays lawn for weeds with PetraTools HD4050.

How to Spray Lawn for Weeds: A Guide for Gardeners

No matter how fastidious of a gardener you are, weeds can still happen in your garden. Dealing with weeds can be very challenging. However, with the right strategies, you can prevent them from invading your lawn. Here’s how to spray your lawn for weeds.

A person sprays lawn for weeds with PetraTools HD4050.

Some weeds are so competitive that they kill the neighboring plants through toxic chemicals. Weed is a plant that causes economic losses or ecological damages, creates health problems for humans or animals, or is undesirable where it is growing.

Think crabgrass, giant foxtail, or common plantain plants, for example.

What are weeds?

With approximately 250,000 plant species worldwide, only about 3% behave as weeds that we don’t want in cultivated land. Weeds aren’t inherently bad. Weeds are good for the ecosystem as it adds organic matter to the soil.

The roots of the weeds stabilize the soil, increasing moisture, creating a secure environment for life. In contrast, the weed’s stems trap organic matter, which breaks down in the soil and sustains other life forms such as insects.

Spraying weeds can be difficult as there are different herbicides to treat different weeds. The herbicides can slightly work or be very different. They can be tolerant or intolerant of different lawn types, and the complications can continue.

Types of Weeds

Have you thought about the weeds you see in your garden?

Where did they come from and why they grow so fast are just a few of the questions we all have about weeds.  Some of them can even cause rashes. If we know what types of weeds are we dealing with, we can provide the appropriate actions for our needs.

  1. Poison Sumac (Toxicodendron Vernix) is a woody shrub or small tree growing to 9 m tall. It usually grows in a swampy area, often next to cattails and Cinnamon ferns. Every part of the plant is poisonous, meaning it can cause serious rashes if touched that produces a burning, itchy rash that can last days to weeks.
  2. Crabgrass (Digitaria) is a plant that has wide, flat blades and produces long flower clusters and thousands of seeds per growing season. Crabgrass will die on its own in the fall, usually after the first frost. However, if you don’t remove it before it disperses its seeds, you’ll have to deal with the weed again the following year.
  3. Dandelions are also known as Leontodon Taraxacum is a flowering herbaceous perennial plant of the family Asteraceae. Their bright yellow flowers often poke up through lawns and appear between cracks in driveways and sidewalks. Their seeds are probably known as those of crabgrass, but dandelions are perennial, not annual weeds. Compared to crabgrass, dandelions have multiple medicinal uses and can be eaten in salads or used to make wine, but still, homeowners prefer to eliminate them.
  4. Plantain Plants are also known as Plantago lanceolata or Plantago major. A plantain can be mowed whenever you mow the lawn. Common plantain has many medicinal uses. Herbalists have considered it a useful remedy for cough, wounds, inflamed skin, and dermatitis. The mashed plantain can be used as a poultice for bee stings, and the leaves can also be dried and made into a tea to treat diarrhea.
  5. Giant Ragweed is a species of flowering plant in the sunflower family. It is widely known in many regions. Giant Ragweed has some ecological value to various insects as a source of food and protective cover. It can develop into a huge plant. It also enables them to live in slightly drier conditions, but the large leaves have a tendency to sag and wither away if there’s a significant drought. Giant ragweed produces up to 1 billion pollen grains, which cause serious allergies.
  6. Wild Madder is called “bedstraw.” This hairless plant has open clusters of creamy star-like yellow flowers with five petals in summer and shiny black inedible berries in winter. The roots of this native wildflower produce a bright pink pigment and were one of the many plants used by the Anglo Saxons for dyeing textiles
  7. Clover Leaf is also known as Trifolium consists of about 300 species of flowering plants in the legume or pea family Fabaceae. These clover plants can be evergreen and are small annual, biennial, or short-lived perennial herbaceous plants.

When to apply weed killer (and how often)

Weeds usually grow actively. Weeds are the problem for gardeners everywhere. There are many tips and procedures to follow when killing them, but cultural practices such as tilling and appropriate fertilization and irrigation can help you control weeds.

If you are using the chemical route, spraying herbicides on your weeds at the right time can help maximize your success in the weed war.

Herbicides are post-emergent or pre-emergent. Post-emergent herbicides control existing weeds, and they can be systemic or non-systemic.

Systemic herbicides work by moving through plants to their roots, and they’re most effective when the plants are actively growing. Glyphosate is a commonly used systemic herbicide.

Non-systemic herbicides damage plant tissues, and they can be applied at any time of day. Pre-emergent herbicides are also effective when applied at any time of day. These herbicides create a chemical barrier in the soil that prevents weeds from appearing.

  • Applying Systemic Herbicides. Applying systemic herbicides at the peak plant growth times during the day increases the herbicides’ effectiveness. Plant growth speeds up and slows down over the course of a day, depending on light level, temperature, and the climate in the location.
  • Early morning and late afternoon are the best times for applying systemic herbicides in summer during warm climates. Don’t apply herbicides around midday or early afternoon in the summer season. Midday heat causes plant growth to slow down, and the herbicides quickly dry out on the leaves, which reduces the number of herbicide weeds absorbed. During winter, weeds continue to grow in warmer areas. So, the best time of day to apply systemic herbicides for this period of time is in the middle of the day, when the temperatures are highest.

  • Cold Climates. Heavy early morning dew can cause herbicides to drain or flow off, so it’s best to apply them after the dew has evaporated. Systemic herbicides work best when applied late morning, midday, and in the afternoon in cool or cold climates.

Tips on spraying lawn for weeds

  • If a lawn was watered or if it rained after applying herbicides, the herbicide would be washed away with the water itself, so be sure that no water will go onto the lawn within a few days of spraying – a few days more would be even better.
  • Remember, plant growth slows down at dusk and speeds up again as the sun rises the following day. After all, prevention is the key to control weeds in your garden.

PetraTools HD4050

Having the right tool for spraying weed killer is a game-changer. A sprayer you can use to kill weeds and also fertilize your plants is definitely worth the investment. That is why we created PetraTools HD4050. It has core features that provide you with the best spraying benefits:

  • Long-Lasting Battery - Our product’s battery is up to four times longer than 2.0 lithium, which other sprayers use. It also has an AC charger that provides power to our sprayer for 8 hours.
  • Multipurpose Attachments - HD4050 has a wand and nozzle that give multiple uses. Both parts cater to all types of spraying solutions, which are great for indoor and outdoor services.
  • Spill-Proof Design - Pouring your solution into our sprayer’s tank is a lot easier. HD4050 has a tank with a wide mouth to prevent messes. You can even see how much solution is left in our tank.
  • Multiple Applications - Because our sprayer’s wand and nozzle cater to all types of spraying needs, you can fertilize, mist, and apply insecticides and pesticides to your plants easily. You can also use our sprayer to disinfect your home more effectively.
  • High Quality - Our backpack sprayer is created to provide the best spraying experience to its users. Its family-owned manufacturer is based in the USA with excellent customer service to provide the best support.


Weeds may be hard to deal with but could be managed effectively with consistency. You just have to know the proper way to spray your lawns so you can get rid of them once and for all.

Having an effective weed killer is also an important factor. Choose one that does not too much to work. An all-natural weed killing solution would be best, one that wouldn’t pose harm to your plants and crops.

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