I’d recommend a self-watering rectangular urban planter box with a built-in reservoir, an overflow drain, and a visible water-level indicator. For a plant killer, the goal is not to find a “magic” pot—it’s to remove the two most common mistakes: underwatering and overwatering. A self-watering box does that by letting the roots draw moisture from a reservoir while the overflow keeps the soil from turning into a swamp. Good options include the Lechuza Balconera and the Glowpear Urban Garden; both are designed for balconies and small urban spaces. If you prefer a generic shopping list, look for a 24–36 inch long box, 10–12 inches deep, made from UV-resistant recycled plastic or powder-coated aluminum, with raised feet, a removable drainage plug, and a water-level indicator.
Why this type? First, it’s forgiving. If you forget to water for a few days, the reservoir gives the plant a buffer. If you tend to “love” plants too much, the overflow drain gives excess water somewhere to go. Second, it’s easier to read: a water-level indicator tells you when to refill instead of guessing. Third, it suits urban spaces: a rectangular box fits balconies, railings, and narrow patios, and casters or raised feet make it easy to move. Avoid tiny decorative pots and sealed containers with no drainage—they make watering mistakes more severe. Also avoid clear reservoirs if algae bother you; look for opaque or tinted reservoirs.
For plants, choose forgiving varieties: snake plant, ZZ plant, pothos, spider plant, or rosemary in a very well-draining mix. Fill the planter with a light, airy potting mix—not garden soil—and leave the top inch or two dry between refills. Keep the reservoir filled according to the indicator, but let it run low for a day before refilling, and empty the overflow if water sits. In winter, reduce refills because plants drink less.
So my recommendation is simple: buy a self-watering urban planter box with a reservoir, overflow, and water-level indicator, then pair it with tough plants and a well-draining mix. That combination won’t make you a perfect gardener overnight, but it will forgive the most common mistakes and give your plants a much better chance.