Giving your feline friend a little patch of green indoors is a fantastic way to enrich their environment. Cats often chew on houseplants, sometimes out of boredom, sometimes seeking greens they instinctively crave. Unfortunately, many common houseplants are toxic to cats. Providing a safe alternative like cat grass satisfies this urge safely and can even offer some digestive benefits. Instead of constantly buying those small, often overpriced plastic containers of cat grass, why not build a stylish, sturdy, and reusable planter box yourself? It’s a rewarding project, surprisingly simple, and creates a lovely green addition to your home that your cat will adore.
This tutorial will guide you through creating a simple yet effective wooden planter box specifically designed for growing cat grass. It’s sized perfectly for a sunny windowsill or a convenient floor spot, giving your kitty easy access to their personal salad bar. We’ll cover the materials, the step-by-step construction, planting the seeds, and some basic care tips to keep the grass thriving.
Why Build a DIY Cat Grass Planter?
Sure, you can buy pre-grown grass or kits, but building your own offers several advantages. Firstly, customization. You control the size and look. Want it to match your decor? Stain or paint the wood (using pet-safe finishes, of course!). Need a larger patch for multiple cats? Scale up the dimensions. Secondly, durability. A well-made wooden box will last much longer than flimsy plastic pots. Thirdly, cost-effectiveness. After the initial build, you only need soil and seeds, which are very inexpensive compared to buying new kits repeatedly. Plus, it’s a fun weekend project!
Gathering Your Materials and Tools
Before you start sawing and assembling, let’s get everything together. You don’t need a professional workshop for this; basic tools will do the job.
Materials:
- Wood: Untreated pine or cedar boards are excellent choices. Avoid pressure-treated wood as the chemicals can be harmful if ingested by your cat. You’ll need enough for the sides and bottom. A common size like a 1×4 or 1×6 board (which are actually 0.75 inches thick and 3.5 or 5.5 inches wide) works well. Let’s aim for a finished box roughly 12 inches long, 6 inches wide, and 4-6 inches deep.
- Fasteners: Wood screws (e.g., 1.25-inch decking screws) are ideal. You could use nails and wood glue for extra strength, but screws alone are usually sufficient. Ensure they are suitable for outdoor/wood use to prevent rusting, although the liner will offer protection.
- Planter Liner: A heavy-duty plastic sheet (like a thick trash bag or pond liner remnant) or a pre-formed plastic planter insert that fits snugly inside your wooden box dimensions. This is crucial to protect the wood from moisture and rot.
- Potting Soil: Choose an organic potting mix suitable for edibles or herbs. Avoid mixes with added chemical fertilizers or pesticides.
- Cat Grass Seeds: Wheat, oat, barley, or rye seeds are commonly sold as ‘cat grass’. You can buy specific cat grass seed mixes or just plain organic seeds of these types from gardening or health food stores.
- Optional: Sandpaper (medium grit), pet-safe wood sealant or paint, small pebbles or gravel for drainage.
Tools:
- Measuring Tape
- Pencil
- Saw: A hand saw is fine, but a mitre saw or circular saw will make quicker, cleaner cuts.
- Drill: With drill bits for pilot holes (slightly smaller than your screw diameter) and a screwdriver bit (or just a screwdriver).
- Staple Gun (Optional): Useful for securing the plastic liner.
- Safety Glasses: Always wear eye protection when cutting or drilling wood.
- Gloves (Optional): Protect your hands.
Building the Planter Box: Step-by-Step
Okay, let’s get building! We’ll aim for a simple rectangular box. For our example (12″ L x 6″ W x 5.5″ H using 1×6 boards), you’ll need to cut your wood pieces.
Step 1: Cut Your Wood Pieces
Using your saw and measuring tape, carefully cut the following pieces from your 1×6 board (which is 5.5″ wide):
- Two (2) Side Pieces: 12 inches long.
- Two (2) End Pieces: 4.5 inches long (This is the 6-inch external width minus two times the thickness of the side boards, which is 0.75″ x 2 = 1.5″).
- One (1) Bottom Piece: 10.5 inches long (This is the 12-inch external length minus two times the thickness of the end boards, 0.75″ x 2 = 1.5″). The width should already be 5.5 inches if you’re using a 1×6 board ripped appropriately or pieced together. Alternatively, cut multiple slats to form the bottom, leaving small gaps for drainage if you aren’t using a solid liner. For this guide, we’ll assume a solid bottom piece cut to fit snugly inside the frame. A simpler bottom is to cut it to the full external dimensions (12″ x 6″) and attach the sides *around* it. Let’s go with that simpler method for clarity:
- Revised Bottom Piece: 12 inches long x 6 inches wide. You might need to join two pieces of 1×4 side-by-side or use a piece of thin plywood cut to size (ensure it’s untreated). For simplicity, let’s re-specify using 1×4 boards (3.5″ high) for a shallower box:
Revised Plan using 1×4 (3.5″ high) boards for a 12″ L x 6″ W x 3.5″ H box:
- Two (2) Side Pieces: 12 inches long (from 1×4 board)
- Two (2) End Pieces: 6 inches long (from 1×4 board)
- One (1) Bottom Piece: Cut from a wider board or plywood to be 12 inches long x 6 inches wide. Or, cut three pieces of 1×4 to be 6 inches long each, and place them side-by-side to make the bottom (total width approx 4.5″, leaving gaps, adjust side pieces accordingly – this gets complicated. Let’s stick to a solid base).
Let’s simplify entirely. Easiest method: Overlapping ends.
- Cut from 1×4 (3.5″ high) board:
- Two (2) Side Pieces: 12 inches long
- Two (2) End Pieces: 6 inches long
- One (1) Bottom Piece: Plywood or solid board cut to 10.5 inches x 4.5 inches (to fit *inside* the assembled frame).
Sand It Smooth: Lightly sand all cut edges and surfaces to remove splinters and rough spots. Your cat might rub against this box, so smooth is good.
Step 2: Assemble the Frame
Now, let’s form the rectangle. Take one 12-inch side piece and one 6-inch end piece. Stand them up to form an ‘L’ shape, ensuring the end of the 6-inch piece butts up against the *inside* face of the 12-inch piece.
Drill Pilot Holes: Drill two pilot holes through the 12-inch piece and into the end grain of the 6-inch piece. Pilot holes prevent the wood from splitting when you drive in the screws.
Attach with Screws: Drive two 1.25-inch wood screws through the pilot holes to join the pieces.
Repeat: Attach the second 6-inch end piece to the other end of the same 12-inch side piece in the same manner. Then, attach the remaining 12-inch side piece to the open ends of the two 6-inch pieces, completing the rectangular frame. Double-check that it’s reasonably square.
Step 3: Attach the Bottom
Place your assembled rectangular frame upside down on your work surface. Position the 10.5″ x 4.5″ bottom piece so it fits snugly inside the frame.
Drill Pilot Holes: Drill pilot holes down through the sides/ends of the frame and into the edges of the bottom piece. Aim for two screws per side/end, staggered slightly.
Secure the Bottom: Drive screws through the pilot holes to firmly attach the bottom piece to the frame. Flip it over – you have a box!
Step 4: Prepare for Drainage (Optional but Recommended)
If your liner won’t have drainage holes (like a solid plastic sheet), it’s wise to drill a few small (1/4 inch) drainage holes in the wooden bottom piece *before* adding the liner. This allows excess water to escape if the liner ever leaks or if you overwater significantly. If using a pre-formed insert with drainage holes, ensure the wooden box also has holes aligned.
Step 5: Add the Liner
This step is vital for longevity.
- If using a plastic sheet: Cut a piece significantly larger than the box interior. Drape it inside, pushing it into the corners. Fold the excess neatly over the top edges of the wooden box. Use a staple gun to secure the liner just below the top edge on the *inside* of the box, or fold it over the top edge and staple on the outside if you prefer. Trim any excess plastic carefully. If you drilled drainage holes in the wood, carefully puncture corresponding small holes in the plastic liner above them using a skewer or nail.
- If using a pre-formed insert: Simply place the insert into the wooden box. It should fit snugly. If it has drainage holes, ensure they align with any holes you drilled in the wood base.
Important Safety Note: Always use untreated wood like pine or cedar. Pressure-treated wood contains chemicals that can be toxic to cats if they chew on the planter box itself. Also, if you decide to paint or seal the wood, ensure you use a product explicitly labeled as pet-safe or non-toxic once cured. Allow ample drying and curing time before adding soil and seeds.
Step 6: Finishing Touches (Optional)
If desired, you can now apply a pet-safe wood sealant or paint to the exterior of the box for aesthetics and extra weather protection (especially if it might get splashed). Follow the manufacturer’s instructions regarding drying times before proceeding.
Planting Your Cat Grass
Your beautiful planter box is ready! Now for the fun part – planting the grass.
Step 1: Add Drainage Layer (Optional)
If you’re concerned about overwatering, you can add a thin layer (about half an inch) of small pebbles or gravel at the very bottom of the lined planter before adding soil. This helps ensure water doesn’t pool around the roots.
Step 2: Fill with Soil
Fill the lined planter box with your chosen organic potting mix, leaving about an inch of space at the top. Gently pat the soil down, but don’t compact it too tightly.
Step 3: Sow the Seeds
Generously sprinkle the cat grass seeds over the surface of the soil. You want dense coverage for a lush patch of grass. Aim for a layer where seeds are close but not deeply piled on top of each other. Gently press the seeds into the soil surface or cover them with a very thin layer (about 1/4 inch) of additional soil.
Step 4: Water Gently
Water the seeds thoroughly but gently. A spray bottle set to mist or a watering can with a gentle rose attachment works best. You want the soil to be evenly moist but not waterlogged. Consistent moisture is key for germination.
Step 5: Find the Right Spot
Place the planter box in a location that receives bright, indirect sunlight. A sunny windowsill is often ideal. Direct, intense sunlight might scorch young seedlings.
Caring for Your Cat Grass
Cat grass grows quickly! You should see sprouts within a few days.
- Watering: Keep the soil consistently moist, especially during germination. Once the grass is established, water when the top inch of soil feels dry. Avoid letting it completely dry out or become soggy.
- Sunlight: Continue providing bright, indirect light. Rotate the box occasionally if it’s leaning towards the light source.
- Trimming: Once the grass reaches about 4-6 inches tall, it’s ready for your cat! You can also trim the grass with scissors occasionally if it gets too long or starts to yellow at the tips. This can encourage new growth.
- Replanting: Cat grass doesn’t last forever. It will eventually yellow and die back after a few weeks. The beauty of your DIY planter is that you can easily pull out the old grass and roots, refresh the soil if needed, and sow a new batch of seeds. Consider having two boxes and rotating them, so your cat always has fresh grass available.
Verified Seed Safety: Common cat grass varieties like wheatgrass, oat grass, barley grass, and ryegrass are widely recognized as safe for feline consumption. They provide roughage which may aid digestion and help with hairball passage. Always source seeds from reputable suppliers, preferably organic, to avoid pesticide residues.
There you have it! A sturdy, attractive, and reusable cat grass planter box made with your own hands. It’s a simple project that provides ongoing enrichment for your indoor cat, satisfies their natural urge to chew greens safely, and adds a touch of living nature to your home. Your feline companion will surely thank you for their personal patch of green goodness. Enjoy watching them nibble away!
