Does Cedar Need to Be Sealed? How to Stain and Protect Outdoor Cedar

Cedar doesn't need to be sealed to resist rot, because Western red cedar contains natural oils that help protect it from decay and insects. But if you want to keep its warm reddish color, reduce surface checking, and slow weathering, you should finish it. Left unfinished, cedar turns a soft silver gray within a season or two. A penetrating oil-based semi-transparent stain is the most popular finish for outdoor cedar because it adds UV protection without forming a film that can peel.

This guide explains when to seal cedar, which finishes work best outdoors, how to stain cedar step by step, and how to care for cedar planters, furniture, and garden structures.

Should You Seal Cedar or Leave It Natural?

Both are valid choices. Many people love the silver patina, and it's a natural part of how cedar ages.

Best Finishes for Outdoor Cedar

Penetrating Oil-Based Semi-Transparent Stain

This is the go-to choice for most cedar projects. It soaks into the wood, shows the grain, adds pigment that blocks some UV, and won't peel. Brushing it on gives the best penetration.

Water-Repellent Preservative

A clear water repellent with a mildewcide reduces moisture absorption and helps fight mildew. It keeps cedar's natural look but doesn't stop graying for long, and it typically needs reapplying every year or two.

Solid-Color Stain

Solid stain hides the wood's natural color but leaves some texture. It lasts longer than semi-transparent stain and works well when you want a painted look.

Paint

A quality 100% acrylic paint over a stain-blocking primer gives the most surface protection, but it hides the wood completely and eventually needs scraping and repainting.

What to Avoid

Clear film-forming finishes like varnish, polyurethane, lacquer, and shellac are not recommended outdoors. UV light passes through and breaks down the wood beneath, and the film eventually cracks and peels.

How to Stain Cedar Step by Step

1. Check the weather. Pick a dry stretch with mild temperatures, and avoid staining in direct midday sun.
2. Clean the wood. Remove dirt and mildew with a mild detergent or a wood cleaner. Use a mildew remover if you see dark spots, since stain won't fix mildew.
3. Let it dry completely. Stain needs dry wood to soak in.
4. Test first. Try the stain on a hidden spot to check the color.
5. Brush it on. Apply with the grain using a quality brush, working a few boards at a time to avoid lap marks.
6. Wipe off the excess. Follow the manufacturer's directions for back-brushing or wiping so the finish doesn't stay tacky.
7. Add a second coat if recommended. Rough or textured cedar often benefits from two coats.
8. Dispose of rags safely. Oil-soaked rags can self-ignite. Lay them flat to dry outdoors or follow the product label.

How Often Should You Reseal Cedar?

There's no single schedule, because sun, rain, and the product all affect how long a finish lasts. A simple test: sprinkle water on the wood. If it beads up, the finish is still working. If it soaks in or the color has faded, it's time to clean and recoat. Horizontal surfaces like seats and tabletops usually need attention sooner than vertical ones.

Caring for Specific Cedar Projects

Cedar Planter Boxes

If you're growing herbs or vegetables, leave the inside of the planter unfinished and stain only the outside. Untreated cedar is a popular choice for edible gardens for exactly this reason. Browse cedar planter boxes, or see our planter box ideas.

Cedar Furniture and Picnic Tables

Seats and tabletops take the most sun and spills. Clean them each spring and recoat when water stops beading. The 6 ft Cedar Picnic Table and cedar A-frame porch swing both benefit from a yearly check. See our general tips on maintaining outdoor furniture.

Arbors, Pergolas, and Bridges

Larger structures should be inspected for loose hardware and any soft spots where wood meets soil. Keep plants trimmed so leaves don't trap moisture against the wood. Our guide to maintaining a wooden pergola applies to garden arbors and garden bridges too.

Tips to Make Cedar Last Longer

• Keep cedar off wet soil where possible, using feet, pavers, or a gravel base.
• Use stainless or hot-dipped galvanized fasteners to prevent dark iron stains.
• Clean off leaves and debris that hold moisture.
• Let water drain freely from planters.
• Store or cover furniture in harsh winters if you can.

Comparing cedar to other woods? See how cedar compares with teak and poly lumber, or shop the full All Things Cedar collection.

Cedar Sealing FAQs

Does cedar need to be sealed?

Not to resist rot. Cedar's natural oils help protect it. Sealing or staining is about keeping its color and slowing weathering and surface checking.

What happens if you don't seal cedar?

It weathers to a silver gray color. Many people like this look, and it doesn't mean the wood is rotting.

What is the best finish for outdoor cedar?

A penetrating oil-based semi-transparent stain is the most popular choice. It shows the grain, adds UV protection, and won't peel.

Should I seal the inside of a cedar planter?

If you're growing edibles, leave the inside unfinished and stain only the outside.

How do I know when to reseal cedar?

Sprinkle water on it. If the water soaks in instead of beading, or the color has faded, it's time to clean and recoat.