How Much Does It Cost to Build a Raised Planter Box?
A basic cedar raised planter box for a deck or patio typically costs between $60 and $150 for materials, depending on size, wood species, and how much soil you need to fill it. Pine is the budget-friendly choice at roughly $1.50 to $2.50 per linear foot for standard 2x6 or 2x8 boards, while cedar runs $3 to $5 per linear foot but resists rot far longer — often 10 to 20 years outdoors without any treatment. For most deck planters, cedar is the smarter long-term spend.
A simple 2x4-foot planter box built from 2x6 cedar boards needs roughly 24 linear feet of lumber, which puts the wood cost around $72 to $120. Add a small bag of exterior screws or deck screws ($8 to $15), and you are well under $150 before soil. Filling the box is where costs climb quickly — a quality potting mix or raised-bed soil runs $10 to $16 per bag, and a 2x4-foot box that is 10 inches deep holds around 5 cubic feet, which is roughly 4 to 5 standard bags. Budget $50 to $80 just for soil if you are starting from scratch.
A few items that are easy to overlook: galvanized or stainless exterior screws resist rust and will not streak your wood over time — worth the small upcharge over standard screws. A food-safe pond liner or hardware cloth stapled to the interior bottom protects the wood from constant moisture without blocking drainage. If you plan to use a power drill, a good set of pilot hole bits prevents cedar from splitting. These extras rarely exceed $20 to $30 total but make a real difference in the finished quality and lifespan of the box.
For a deck or patio setting, consider adding caster wheels ($15 to $30 for a set of four heavy-duty outdoor casters) so you can rotate plants toward the sun or move the box when you need to clean the deck. The soil in a fully planted 2x4 box can weigh 80 to 120 pounds, so casters are a practical upgrade, not just a convenience.
Frequently Asked Questions
Cedar vs. pine — which wood should I use for a raised planter?
Cedar is the top choice for outdoor planters because it naturally resists rot, insects, and moisture without any chemical treatment. A cedar box can last 15 to 20 years on a deck. Pine is significantly cheaper but will begin to rot within 3 to 5 years outdoors unless you use pressure-treated wood, which is not recommended for food gardens due to chemical leaching. If budget is tight, pine works fine for flower-only planters — just expect a shorter lifespan.
How many bags of soil do I need to fill a raised planter box?
Calculate the volume of your box in cubic feet: Length (ft) x Width (ft) x Depth (ft). A standard 2x4-foot box that is 10 inches (0.83 ft) deep holds about 6.6 cubic feet. Most bagged potting mix and raised-bed soil comes in 1 to 2 cubic foot bags. Divide your box volume by the bag size to find how many bags you need. For a 2x4x10-inch box, plan on 4 to 7 bags depending on bag size.
Do I need to line the inside of the planter box?
A liner is not required but is highly recommended for wood longevity. Stapling a food-safe pond liner or heavy-duty landscape fabric to the interior walls and bottom keeps moist soil from direct contact with the wood, which can nearly double the life of a pine box and noticeably extends cedar as well. Make sure to leave the very bottom open or poke drainage holes so water does not pool and rot the base boards.
What screws should I use to build a planter box?
Use exterior-grade screws — either hot-dipped galvanized or stainless steel. Standard zinc-plated screws will rust within a season or two outdoors, leaving orange streaks on your wood. For 2x6 boards, 2.5-inch to 3-inch #8 deck screws are the right size. Always pre-drill pilot holes in cedar to prevent splitting, especially near board ends.
Can I build a raised planter box without power tools?
Yes. A hand saw, a drill or screwdriver, and a measuring tape are all you truly need. Pre-cut lumber from a home improvement store eliminates sawing entirely — most stores will make cuts for free or a small fee. Corner brackets make hand-building easier by adding structural rigidity without needing precise joinery. The whole project can be completed with basic hand tools in a couple of hours.