How to make nettle tea: homemade plant fertilizer

TL;DR: Make nettle tea in three steps

Pack nettles in water, let ferment 1-2 weeks, strain, dilute with water, and you have free plant booster. Spray on leaves or pour at roots. No chemicals needed.

What is nettle tea?

Nettle tea (nettle ferment) is a fermentation of nettles in water. The nettles break down, release their nutrition into the water, and you get a strong liquid full of nitrogen, potassium and other nutrients.

This is not the same as tea for drinking. It is more a fermentation - an anaerobic process where bacteria release nutrition. It smells strong and unpleasant; that is normal. The stronger the smell, the better it works.

Why use nettle tea?

Cheap (free if you have nettles in your garden). Organic (no chemicals). Fast-acting (plants see difference within days). Fights weakness and disease (the smell helps against lice and spider mites). Strengthens plants against disease.

Many organic gardeners use it instead of synthetic fertilizers. A single batch of 10 liters of nettle tea can feed your whole garden all summer.

Where do you find nettles?

Nettles grow everywhere: garden, ditch, forest edge, along roads. They have dark green, rough leaves and sting. Pluck carefully (or wear gloves) and put in a bucket.

Summer (May-October) is best. June-July nettles are richest (most nutrition).

You need roughly 1 kg nettles (fresh) per 10 liters water. Not much.

The recipe: nettle tea step by step

Ingredients

• 1 kg fresh nettles (leafy tops, not roots)
• 10 liters water (rainwater, not chlorinated tap water)
• Bucket or vat (not metal; plastic or wood)
• Stirring rod or spatula
• Sieve or old stocking

Preparation

Chop the nettles roughly and place in your bucket. Pour water over. Set the bucket somewhere the smell does not bother neighbors (it smells strong).

Stir once or twice daily. This speeds fermentation.

After 3-5 days you see bubbles - that is fermentation. The smell gets stronger. This is good.

After 1-2 weeks the bubbling stops and the smell becomes stable (less sharp). This means it is ready.

Strain the nettles out. You have a dark green, smelling liquid.

Storage

In a sealed vat you can keep nettle tea for months. The older, the stronger. Sealed it no longer gets worse at smelling.

How do you use it?

Always dilute. Undiluted nettle tea can scorch leaves. Guidelines:

• For leaf spray: 1 part tea + 10 parts water
• For basic feeding (in soil): 1 part tea + 20 parts water
• For weak plants: 1 part tea + 5 parts water

Spray on leaves in the evening (not in full sun). Or pour around roots once per week.

Use it in the growing season (May-September). In winter not needed.

Benefits of nettle tea

1. Free (you pick weeds and make nutrition)
2. Organic (no chemicals)
3. Multipurpose (nutrition, pest control, disease prevention)
4. Fast-acting (visible effect in days)
5. Sustainable (no plastic packaging, no transport)

Step-by-step

Step 1: Collect nettles

Find a place with many nettles. Wear gloves and pluck roughly 1 kg young leaf (plant tops). Place in bucket.

Step 2: Add water

Fill your bucket with 10 liters of rainwater or non-chlorinated water. The nettles will float; that is okay.

Step 3: Let ferment

Set the bucket in the garden, far from your house (it smells strong). Stir daily. Wait 1-2 weeks until bubbling stops.

Step 4: Strain and dilute

Strain the nettles out. Keep the liquid. Dilute carefully when you want to use it (1:10 to 1:20).

Step 5: Use

Spray or pour around plants. For sick plants every 5-7 days. For healthy plants once per week.

Frequently asked questions

Why does nettle tea smell so bad?

The strong odor comes from ammonia and sulfates released during fermentation. This is how you know it is working. If nettle tea does not stink, it probably did not ferment properly.

Can I use dried nettles?

Yes, but it works less well. Fresh is better. Dried nettles release slowly. If you only have dried: use 500 grams per 10 liters and let ferment 2-3 weeks.

Is nettle tea safe for vegetables?

Yes, completely. It is even recommended for vegetable gardens. Do not spray just before harvest (wait at least 1 week), but otherwise no risk.

What if my tea does not ferment?

Check your ingredients. Did you use chlorinated tap water? Chlorine kills bacteria. Rainwater is better. Too cold? Fermentation is slow below 15 degrees Celsius. Wait and stir more.

Can I use nettle tea for pest control?

Yes, definitely. Lice, spider mites, whitefly - they dislike nettle tea. Spray once per 3-4 days until the pest is gone. It is not as strong as insecticide, but helps against mild infestations.

Will weeds grow stronger from nettle tea?

Yes. So direct it at water edges and erosion zones. Not on your ornamental plants, or you feed weeds.

Variations: mix with other ingredients

What gardeners do: add other ingredients for extra strength.

• Comfrey (hoestwortel): much potassium
• Borage: lots of nitrogen
• Herb scraps: vitamins
• Charcoal: absorbs ammonia

Add maximum 20% extra material (else it ferments wrong).

Discover your own garden design

At gardenworld.app you can upload your yard and see which plants are disease-prone. With organic nettle tea you give your garden natural resistance. Plant organic, fertilize organic.