Container Gardening: Complete Guide to Growing in Pots

Grow Anywhere with Containers

Self-watering planters make it easy to grow plants in almost any location.

Container gardening saves space and solves problems: too much shade, poor soil, limited time, mobility issues, or difficult climates. Containers can be more productive than in‑ground beds while avoiding most pests and diseases. Best of all, they bring the garden up close, creating an intimate connection.

Choosing Containers

Almost anything works: terra cotta, plastic, pressed fiber, whiskey barrels, 5‑gallon buckets, bushel baskets, wooden boxes, even old tires. Self‑watering planters with built‑in reservoirs are excellent. Match container size to the plant: radishes need only 6 inches depth, but tomatoes require at least 5 gallons. General rule: use the largest container possible—more soil means more root space and less frequent watering.

Ensure drainage holes (on sides preferred). Elevate pots on bricks if holes are on the bottom. A 20‑gallon pot needs four to six ¾‑inch holes; a 30‑gallon pot needs at least eight 1‑inch holes. Skip the gravel layer—it just wastes root space in a well‑aerated mix.

Soil Mixes

Use a light, friable, well‑drained, moisture‑retentive mix. Garden soil is too dense and brings diseases. Most container plants thrive in a soilless blend of sphagnum moss, vermiculite or perlite, plus compost.

Recipes

• Organic Blend: 5 gal finished compost, 1 gal builder’s sand, 1 gal vermiculite/perlite, 1 cup granular organic fertilizer.
• Standard Blend (Cornell Mix): 1 bushel vermiculite, 1 bushel ground sphagnum moss, 8 tbsp super phosphate, 8 tbsp ground limestone, 2 cups bone meal.
• Light Blend (for rooftops): 5 gal ground sphagnum moss, 5 gal vermiculite/perlite, 2 gal compost, 1 cup granular organic fertilizer.

Replace or refresh mix each season if it becomes compacted. Container Booster Mix can recharge depleted soil.

Caring for Container Plants

Watering Innovations

• Water‑holding crystals (e.g., Terra‑Sorb) absorb 200× their weight, reducing watering by 50–70%.
• Self‑watering containers have a reservoir and wick; add liquid fertilizer to the reservoir.
• Drip‑irrigation systems with a timer automate watering.

Watering Tips

• Start with a moisture‑retentive mix.
• Water until soil is fully moist and water exits drainage holes.
• Mulch large containers with shredded bark, leaf mold, grass clippings, or straw.
• Shield plants from midday heat with lattice, trellis, awning, or umbrella.
• Never use softened water (salts are toxic). Rainwater is best.
• Cluster pots to create a humid microclimate.

Fertilizing

Container mixes provide few nutrients. Add granular organic fertilizer at planting, then feed weekly with half‑strength water‑soluble fertilizer. Foliar feed with seaweed or fish emulsion for a quick boost.

Maintenance

• Weekly: deadhead, pinch back leggy stems.
• Replace tired plants with fresh annuals (ornamental kale, mums).
• Overwinter perennials: cut back, keep cool, water sparingly, no fertilizer until spring. Repot in fresh mix when warm weather returns.

Trellises and Supports

Vertical supports are essential for tomatoes, cucumbers, and flowering vines. Keep scale proportional to the pot and attach securely—losing a mature plant to a storm is heartbreaking.