How to Make a Weed Killer That Kills Insects as Well

Weeds and insects are two of the biggest headaches for homeowners and gardeners. Most commercial products only target one issue—weed killers handle plants, and insect sprays handle pests. Buying both can get expensive and fill your shed with chemicals. The good news is, you can make a homemade solution that tackles both problems using simple ingredients you may already have in your kitchen.

This DIY spray is affordable, effective, and safer for your yard when used correctly.

Why Go Homemade?

Saves money compared to store-bought sprays
Works on both weeds and common pests
Made from easy-to-find household items
Gentler on the environment than harsh chemicals

Ingredients You’ll Need

White vinegar (1 gallon) – High acidity burns weeds and dries them out
Salt (1 cup) – Draws moisture out of weeds and prevents regrowth
Liquid dish soap (1 tablespoon) – Helps the mix stick to leaves
Neem oil (2 tablespoons) – Natural insect repellent that deters aphids, mites, beetles, and more
Optional: Citrus essential oil (10 drops) – Boosts insect-killing power and smells fresh

How to Make It

Pour 1 gallon of white vinegar into a bucket.
Stir in 1 cup of salt until dissolved.
Add 1 tablespoon of dish soap and mix gently.
Stir in 2 tablespoons of neem oil (and citrus oil if using).
Funnel the mix into a spray bottle or garden sprayer.

How to Use It Safely

Spray directly on weeds and insect-infested areas.
Apply on sunny, dry days for best results.
Avoid spraying on grass, flowers, or crops you want to keep—this solution kills any plant it touches.
Reapply every 7–10 days if needed.

Cost Breakdown (2025 U.S. Prices)

Here’s what it costs to make one full gallon batch of the spray in 2025. Prices are averages and may vary depending on location and brand.

Ingredient	Amount Used	2025 Price Range	Cost Per Batch
White vinegar	1 gallon	$3.70–$4.19 per gallon	~$4.00
Salt	1 cup (~8 oz)	$0.50–$1.50 for a full bag	~$0.15
Dish soap	1 tbsp	$2–$5 per bottle (16 oz)	~$0.20
Neem oil	2 tbsp (~1 fl oz)	$8–$12 for 1 oz bottle / $25+ for pint	~$8.00
Citrus essential oil (optional)	10 drops	$5–$15 per bottle	~$0.50

Estimated total: $12.85 per gallon batch (with neem oil as the main cost). If you already have dish soap, vinegar, or essential oils at home, your cost per batch will drop significantly.

By comparison, buying separate commercial weed killers and insect sprays could cost $20–$40, so this mix is competitive and more natural.

Homemade Mix vs. Store-Bought Spray

Here’s how the homemade solution stacks up against a popular store-bought option like Roundup Weed & Bug Killer (Ready-to-Use, 1 gallon, 2025 price ~$20–$25):

Feature	Homemade Weed + Bug Mix	Roundup Weed & Bug Killer (Store-Bought)
Cost per gallon	~$12.85	~$20–$25
Main ingredients	Vinegar, salt, soap, neem oil	Glyphosate + pyrethroids (synthetic chemicals)
Weed effectiveness	Works best on young/small weeds; less effective on deep-rooted weeds	Stronger, kills most weeds including perennials
Insect control	Effective against soft-bodied insects (aphids, mites, beetles)	Kills a wide range, including tougher pests
Eco-friendliness	Natural, biodegradable, safe when used properly	Chemical-based; can harm beneficial insects and pollinators
Safety	Safer for kids & pets once dry	Must be handled carefully, toxic if ingested
Ease of use	Requires mixing at home	Ready-to-use out of the bottle

Summary:
The homemade version is cheaper, eco-friendlier, and safer for families and pets. However, it may require reapplication and won’t be as powerful on large, deep-rooted weeds compared to chemical store-bought sprays.