What To Do With Walnut Hulls

Walnut hulls are the thick, green outer shells that surround the walnut shell itself, and there are plenty of useful things you can do with them instead of tossing them in the trash.
 
If you’ve ever cracked open a batch of black walnuts and ended up with a pile of those staining hulls, you might be wondering what to do with walnut hulls once the nuts are out.
 
The good news is that walnut hulls are far from waste, and people have been using them for centuries in gardens, homemade dyes, and even natural remedies.
 
In this post, we’ll walk through the best ways to use walnut hulls, from the practical to the creative, so you can put every part of your harvest to work.
 
Let’s dig in.
 

What to Do With Walnut Hulls: Practical Uses

There are so many things you can do with walnut hulls, and here are some of the most popular and useful options:

1. Make a Natural Dye

One of the oldest uses for walnut hulls is turning them into a rich, brown dye.
 
Walnut hulls contain juglone, a compound that produces deep brown and black tones that bond beautifully to fabric, yarn, and even wood.
 
You simply simmer the hulls in water, strain the liquid, and soak your material until you get the shade you want.
 
This is a favorite project for anyone who loves natural dyeing, and the results are gorgeous and long-lasting.
 

2. Create a Wood Stain

If you work with wood, walnut hulls can double as a homemade stain.
 
Boil the hulls to make a concentrated liquid, then brush it onto bare wood to give it a warm, antique brown finish.
 
It’s a chemical-free alternative to store-bought stains, and using walnut hulls this way adds a beautiful, natural touch to furniture and crafts.
 

How to Use Walnut Hulls in the Garden

Gardeners have plenty of reasons to hold onto walnut hulls because they can be surprisingly helpful outdoors:

1. Natural Pest Deterrent

Walnut hulls contain juglone, which many insects and pests find unpleasant.
 
Sprinkling crushed walnut hulls around your garden beds can help repel certain bugs and grubs.
 
Just be mindful, because juglone can also harm some sensitive plants, so use walnut hulls thoughtfully and keep them away from tomatoes and other vulnerable species.
 

2. Mulch and Compost

You can add walnut hulls to your compost pile or use them as a rough mulch around tough, juglone-tolerant plants.
 
They break down slowly, adding organic matter to the soil over time.
 
Because they decompose gradually, walnut hulls make a durable mulch that helps suppress weeds and retain moisture.
 

3. Keep Them for Seed Starting

Some gardeners use ground walnut hulls in potting mixes to improve drainage.
 
Mixing a small amount into your soil can help aerate it, though you should always test how your particular plants respond before going all in.
 

Creative and Household Ways to Reuse Walnut Hulls

Beyond the garden, there are plenty of clever household uses for walnut hulls that you might not have considered:

1. Homemade Abrasive Cleaner

Ground walnut hulls are a mild abrasive, which makes them handy for scrubbing tough grime off surfaces.
 
You can sprinkle crushed walnut hulls onto a damp cloth and use them to scour pots, tools, and outdoor furniture.
 
Just avoid using them on delicate surfaces that scratch easily.
 

2. Natural Ink and Arts

Artists have long used walnut hulls to make ink for drawing and calligraphy.
 
The same dye liquid you make for fabric works wonderfully as a dark brown ink.
 
It’s a fun, eco-friendly way to create your own art supplies from something you’d otherwise throw away.
 

3. Fire Starters

Dried walnut hulls burn well and can be used as kindling or added to homemade fire starters.
 
They light easily and give off steady heat, making them a smart addition to your camping or fireplace supplies.
 

4. Natural Body Scrub

Because of their gritty texture, finely ground walnut hulls are sometimes used in exfoliating scrubs.
 
Mixed with a little oil or soap, they help slough off dead skin, leaving you feeling refreshed.
 
Always test a small patch of skin first, since walnut hulls can be irritating for some people.
 

Things to Know Before Using Walnut Hulls

Before you dive into reusing walnut hulls, keep a few important cautions in mind:

1. Watch Out for Stains

Walnut hulls stain almost everything they touch, including your hands.
 
Wear gloves when handling fresh walnut hulls, and protect your work surface with old newspapers or a drop cloth.
 

2. Be Careful With Juglone

Juglone is toxic to some plants and can be an irritant to pets and people in large amounts.
 
Use walnut hulls in moderation, and keep them out of reach of curious animals.
 

3. Dry Them Properly

If you plan to store walnut hulls, dry them thoroughly first to prevent mold.
 
Spread them out in a warm, airy spot until they’re completely dry, then keep them in a breathable bag or container.
 

So, What to Do With Walnut Hulls?

Walnut hulls are a versatile, natural resource that you can turn into dye, wood stain, garden helpers, cleaners, and even art supplies.
 
Instead of throwing them away, you can reuse walnut hulls in dozens of practical and creative ways around your home and garden.
 
Just remember to handle them with care, respect their staining power, and be mindful of juglone around sensitive plants and pets.
 
With a little imagination, those humble walnut hulls can become one of the most useful parts of your harvest.