I used to see weeds as nothing but trouble—until I discovered they can actually help my garden thrive. Turning those pesky invaders into homemade fertilizer feels like a win-win.
It’s a smart, budget-friendly way to boost plant growth without heading to the store. I’ve tried a bunch of methods, and some are way easier than you’d think.
Here’s how to turn yard weeds into garden gold and get the most out of your natural fertilizer.
1. Compost Tea Brewing
Fill a bucket with weeds and cover with water, letting it steep for 1-2 weeks with occasional stirring. The resulting dark liquid contains nutrients leached from the decomposing plants. Strain out the plant material when the water turns brownish.
Dilute this potent brew at a 1:10 ratio with water before applying around your plants. Pour it directly onto soil around plant bases, avoiding leaves to prevent potential leaf burn. This gentle, nutrient-rich solution feeds plants gradually.
2. Weed Mulching
Simply lay freshly pulled weeds directly around garden plants, making sure to remove any seed heads first. The weeds will break down over time, returning nutrients to the soil while suppressing new weed growth and retaining moisture.
Apply a 2-3 inch layer around plants but keep it from touching stems to prevent rot. This method works best with young, tender weeds that haven’t gone to seed. The mulch gradually decomposes, feeding your soil throughout the growing season.
3. Fermented Weed Juice
Chop weeds finely and place in a container with equal parts water and a tablespoon of molasses. Cover loosely and let ferment for 7-10 days, stirring daily. The molasses feeds beneficial microbes that break down the plant material.
When bubbling stops, strain the mixture and dilute the liquid at a 1:20 ratio before applying. This potent brew delivers nutrients and beneficial microorganisms directly to your soil. Apply monthly during the growing season for best results.
4. Weed Ash Application
Burn completely dried weeds in a metal container until they turn to white ash. Let cool thoroughly before collecting. The burning process concentrates minerals like potassium, phosphorus, and calcium while eliminating weed seeds.
Sprinkle a thin layer of ash around alkaline-loving plants or mix into compost. Use sparingly as ash is highly alkaline and can raise soil pH. Avoid using around acid-loving plants like blueberries, and never use on seedlings which can be damaged by its strength.
5. Nitrogen-Rich Nettle Tea
Harvest stinging nettles wearing gloves and stuff them into a bucket, covering with water. Let steep for 1-3 weeks until the water turns dark and smelly. The fermentation releases nitrogen and minerals from this nutrient-dense weed.
Dilute the finished brew at a 1:10 ratio before applying to heavy-feeding plants like tomatoes and corn. This powerful nitrogen boost stimulates leafy growth. Apply biweekly during the growing season for spectacular results with vegetables and flowering plants.
6. Weed-Based Bokashi
Layer chopped weeds with bokashi bran (containing beneficial microorganisms) in an airtight bucket. Press down firmly after each layer to remove air. The anaerobic fermentation process preserves nutrients while breaking down the plant material.
After two weeks, bury the fermented material in trenches between plants or add to compost. This method quickly transforms weeds into plant-available nutrients without the long wait of traditional composting. The bokashi process even neutralizes weed seeds while preserving maximum nutrients.
7. Dandelion Root Soaking
Collect dandelion roots, wash thoroughly, and chop into small pieces. Soak in water for 24 hours to extract minerals like iron, calcium, and potassium that these deep-rooted weeds pull from far below the soil surface.
Strain the liquid and apply directly to plants that need a mineral boost. The remaining root pieces can go into your compost pile. This method taps into dandelions’ superpower of mining deep soil nutrients that shallow-rooted plants can’t reach, making these nutrients available to your garden.
8. Green Manure Trench
Dig a 12-inch deep trench between garden rows and fill with freshly pulled weeds. Cover with soil and plant alongside it. As the weeds decompose underground, they release nutrients directly where plant roots can access them.
This method works especially well for heavy feeders like corn and squash. The decomposing weeds create a slow-release fertilizer zone while improving soil structure. This technique mimics traditional green manuring but uses unwanted weeds instead of cover crops.
9. Purslane Foliar Spray
Blend fresh purslane with water at a 1:4 ratio until smooth. Strain through cheesecloth and transfer to a spray bottle. This common weed is exceptionally high in beneficial omega-3 fatty acids and antioxidants.
Spray directly onto plant leaves in the early morning for quick nutrient absorption. The fine mist delivers trace minerals directly to leaves where they’re quickly absorbed. Purslane’s high mucilage content helps the spray adhere to leaves, making it an effective delivery system for micronutrients.
10. Weed Composting Layer Cake
Create alternating layers of weeds and high-carbon materials like dried leaves or newspaper in your compost bin. Keep layers thin (about 2-3 inches) and sprinkle soil between each to introduce decomposer organisms.
Water the pile until moist but not soggy and turn every few weeks. This layering technique speeds decomposition by creating ideal carbon-to-nitrogen ratios. The finished compost will be ready in 3-6 months, providing a balanced, nutrient-rich amendment perfect for garden beds and potting mixes.
11. Chickweed Liquid Fertilizer
Fill a bucket halfway with chickweed, a nutrient-dense weed rich in copper, iron and phosphorus. Add water to cover completely and place a weight on top to keep the plant material submerged. Let ferment for 10-14 days.
Strain the liquid and dilute at a 1:5 ratio before applying around plant bases. Chickweed’s high saponin content creates a natural soap-like effect that helps nutrients penetrate soil. This gentle fertilizer is perfect for seedlings and young plants that need a gentle nutrient boost.
12. Weed Seed Removal Composting
Place weeds with seed heads in a black plastic bag, add a cup of water, and seal tightly. Leave in direct sunlight for 4-6 weeks. The heat generated kills seeds while preserving nutrients in the plant material.
After the cooking period, add the sterilized weeds to your regular compost pile. This method allows you to safely compost even the most persistent weeds without risking spread. The high-temperature decomposition also helps break down tough stems and roots more quickly.
13. Clover Nitrogen Fixation
Rather than removing clover from lawn areas, mow it regularly and leave the clippings in place. Clover naturally fixes nitrogen from the air into the soil through specialized root nodules, essentially creating free fertilizer.
For garden beds, harvest clover from lawn edges, chop finely, and work into the top inch of soil. The plant material breaks down quickly while releasing nitrogen. This method harnesses clover’s unique ability to make atmospheric nitrogen available to other plants.
14. Weed-Infused Compost Activator
Collect nitrogen-rich weeds like lamb’s quarters and chickweed. Blend with water and a spoonful of sugar to create a slurry. This mixture jump-starts microbial activity in slow compost piles.
Pour one cup of this activator over each new layer of materials in your compost bin. The high nitrogen content and easily accessible nutrients feed decomposer organisms. This technique can cut composting time in half while ensuring weeds contribute their nutrients to your garden system.
15. Horsetail Mineral Extract
Gather horsetail plants and dry completely in a well-ventilated area. Once dry, simmer a handful in a gallon of water for 30 minutes. This extracts silica and other minerals from this ancient plant.
Let cool, strain, and dilute 1:5 before spraying on plants. The high silica content strengthens cell walls, making plants more resistant to pests and disease. This extract works particularly well for tomatoes, cucumbers, and other plants susceptible to fungal issues.