I wanted to bring some greenery to the front of our house with the addition of some large planters. After looking at some different options, I decided to build some Cedar Planters. 
This project ended up taking way longer than anticipated, but even so, I am extremely happy with how they turned out and had to share. Keep reading to find out all the challenges involved in building these beautiful Cedar Planters.
Cedar Planters – Self Watering SIP Planters
We recently moved into a beautiful new home in a newly developed neighborhood. These new developments are designed with so much concrete and being new the gardens are young and the few boulevard trees that have been planted are still small.
Our neighborhood is built on the side of a rock mountain and as such the ground is mostly rock and gravel. We found this out after digging a few holes in an attempt to plant some trees. The ground is boulders and crushed stone covered with a skiff of topsoil, not ideal. Rather than try to remove the boulders and plant them in the ground, I decided to build some large Cedar Planters.
Concrete VS Wood
Initially, I was focused on the idea of building concrete planters but ultimately decided on wood due to the size and cost of building concrete planters.
Tree Choice – Emerald Cedar
Big enough to block some wind, create a privacy screen, and have wow, a real statement piece!
The three main criteria for tree choice were, that one, they must be evergreen. The plant needs to look good, all year round. Two, it needs to grow well in a pot. And three, low cost, I really didn’t want to spend $50 to $100 per tree. Answer…
Emerald Cedar / THUJA OCCIDENTALIS ‘SMARAGD’
I always liked the look of these small evergreen trees and as fate would have it, my local superstore garden center happened to have 5” emerald cedar on sale for $10 each. This was a bargain as other garden centers in the area were charging $25 at the time. It was meant to be. 
Cedar Planters Design Challenges
Material Choice
This one is pretty obvious given the title, but Cedar will be our wood type of choice. 1×6 Cedar Fence Boards will make up the walls and 2×2 Cedar Balusters are used for structural pieces in the corners.
Corner Wood Joints – Mitred Butt Joint
The easiest way to do the corner wood joints is with a basic Butt Joint. Using Butt Joints would take a fraction of the time. That being said, even though the Butt Joint is quick and easy, we instead opted to use a Mitred Butt Joint, and reinforce it with glue and a backing piece.
Planter Liner – Heavy Duty Garbage Bags
There are three main reasons why we decided to put a liner into these planters.
- We want to space the fence boards leaving a gap between each board. Without the liner, the dirt fill will spill out through the gaps.
- Wood treatment, we will be treating the wood with a waterproofing wood oil. Using a liner we don’t have to worry about this wood treatment poisoning our new plants.
- The base of these cedar planters will feature a SIP Self Watering System. This will work by draping the liner into a plastic tote mounted inside the bottom of the planters. The tote will be filled with crushed aluminum cans and some garden mesh
Heavy Duty Garbage Bags For The Win!
As it turns out, heavy-duty, contractor-grade garbage bags fit the dimensions of our planters almost perfectly.
SIP Self Watering Planter System
Self-watering planters or Sub-Irrigation Planters (SIP) use the bottom of the planter as a reservoir. The planter fill sits above this reservoir and a small portion of the fill is funneled down into the reservoirs acting as a siphon to migrate water up into the main planter and plant roots.
Are Thuja occidentalis ‘Smaragd’ Good For (SIP) Self Watering Planters?
While it is not recommended to grow Thuja occidentalis ‘Smaragd’ in Self Watering Planters, I have other Emerald Greens growing in SIP planters and they are thriving. For this reason, I have decided to throw caution to the wind and go ahead with it anyway.
Drainage System To Drain Runoff Away.
Having the SIP reservoir tub means I can design a drainage system so runoff won’t stand underneath the planters. This will keep my concrete and deck clean as well as help to stave off that beautiful, green, PNW Moss😉
Cedar Planters Wood Treatment
With most of my wood projects, I like to use a two-in-one stain and polyurethane from either Minwax or Varathane. It stains to your choice of color while completely sealing out moisture with a solid polyurethane coating. This is great for indoor projects or finishes that won’t be constantly exposed to sunlight, as the polyurethane will crack and become degraded over time. For this reason, I decided to stray from my normal wood finish of choice and try Waterproofing Wood Finish Penetrating Oil instead.
BEHR DECKPLUS Transparent Waterproofing Wood Finish Penetrating Oil
Designed to give long-lasting UV and water protection, BEHR DECKPLUS Transparent Waterproofing Wood Finish Penetrating Oil should be just what we need.
Building Cedar Planters – Time To Get To Work
The Tools
- Ryobi Sliding Mitre Saw
- Milwaukee 12v Drill Driver
- Bit Driver Set
- Bar Clamps for WoodWorking (Quick Clamps)
- 2” Disposable Paint Brushes
- PVC Tubing Cutter
- Heavy Duty Staple Gun
The Parts and Materials
- 1 5/8” Deck Screws
- Cedar Fence Boards
- Lepage Outdoor Weatherproof Wood Glue
- BEHR DECKPLUS Transparent Waterproofing Wood Finish Penetrating Oil
- Varathane One-Step Stain & Polyurethane
- 3 Mil 42 Gallon Heavy Duty Garbage Bags
- PVC Glue and Primer
- ½” PVC Pipe and Assorted Fittings
- ½” Bulkhead Fittings
- Plastic Tote
The How – Building DIY Cedar SIP Planters
Step-1 Cutting The Wood
We have a little Ryobi Sliding Mitre Saw that makes light work when cutting the cedar fence board to length. That said, it wasn’t that simple. Here are some of the challenges we faced.
- Bulk Volume = Time Consuming more planters means more time on the saw.
- Not a perfect 45-degree cut. Cutting angles for the miter joint corners required a little finesse. Care had to be taken when setting the angle of the saw as the locking point for 45degrees seems
- Fence boards have a Rough Side and a Smooth Side. Cutting to wood in a way that all exterior faces are smooth would have taken even more time. Instead, we opted to make the least amount of cuts and adjustments. The result is a mix of smooth and rough.
Step-2 Glue and Screw
I used Lepage Outdoor Weatherproof Wood Glue on all mating surfaces. I’ve used it previously so I know this stuff is strong. Drilling Pilot holes prevents the wood from splitting when installing the screws. Glew and screw to ensure they don’t come apart prematurely. 
Step-3 Stain and Seal
Next, two coats, inside and out, using Behr’s DECKPLUS, Transparent Waterproofing Wood Finish Penetrating Oil. I had never used Penetrating oil before, so I was thrown by the consistency. Like water. I let gravity help the penetration by moving the planter so the application side was always facing up.
Step-4 Feet
Because the feet could regularly be damp during the winter, I decided to coat them with polyurethane. A little extra to seal out moisture and prevent rot. 
Step-5 Drain Pan / SIP Reservoir
The Drain Pan / SIP Reservoir is made with a cheap plastic tote from Princess Auto. A bulkhead fitting in the bottom allows for a drain pipe to be connected. For the siphon, we cut holes in plastic takeout cups and glued them to the bottom of the plastic tote. The pipe in the middle is the overflow, this will drain runoff away from underneath the planter. 
Step-6 Planter Liner
I did not plan this, but conveniently, a garbage bag is an almost perfect fit. The bag is first folded inside itself and then it is stretched over the lip. 
I added a strip of plastic strapping as well as a little tape for reinforcement while planting. Once planted, the lip is folded over and held down with some decorative bark mulch. 
Our DIY Cedar Planters Are ✅
This project ended up taking way more time than I had anticipated. That being said, the plastic liner, drainage, and SIP system will make them last longer while helping the plants thrive, and the wood treatment gives them a quality finish that looks 👌. All said and done, I am extremely proud of how they turned out and I’m happy I put in the effort!
DIY Cedar Planters Video
See more pictures and videos from this project featured on the garden_gainz Instagram channel. 😀
Are you interested in seeing more of my home projects? Did I miss something? Drop a comment in the comments box below 👇
More From Weekender Van Life
Some Of Our Most Rewarding And Useful Projects
How We Heat Our Van During Winter Adventures
- Gasoline Parking Heater Installation
- Chinese Parking Heater Webasto Copy
- Van Heater Air Duct System – Update / Upgrade
All Powered Up
As always, thank you for taking the time to visit Weekender Van Life. And remember, always take the road less traveled!
Weekender Van Life – Van Life Blog – weekendervanlife.com
Leave a Reply