Grow Spaces
Kratky on a Balcony or Patio
Outdoors, Kratky containers get all the light they could want. They also get rain, heat, wind and insects, and each one needs a plan.
The Outdoor Trade-Off
Full sun lets you grow crops a windowsill can't handle. The catch is that a Kratky container is a still pool of nutrient water sitting outside, so weather and wildlife affect it more than they would a pot of soil.
We use the warm months this way too: plants that spent the winter in jars indoors go outside once the weather warms up.
Rain
Rain can run into net cup holes, dilute the nutrient solution and, worse, refill the air gap the upper roots depend on. Use containers with lids that cover everything except the net cups, place them under an overhang if you can, and check levels after heavy rain.
Heat
Sun on a container heats the solution. Warm water holds less oxygen, and warm, still water encourages root rot. Use light-colored or wrapped containers, keep them in shade even when the leaves are in sun, and choose larger containers, which warm up more slowly.
Wind
As plants grow and the solution level drops, containers get top-heavy. Use wide, stable containers, group them together, and stake or tie taller plants.
Mosquitoes
Any gap around a net cup is an opening to standing water, and mosquitoes will lay eggs in it. Make sure net cups fit snugly and seal or cover any other openings.
What Grows Well
- Leafy greens and herbs in spring and fall, when it's cooler
- Larger, warm-season plants in summer, in big containers with room for plenty of solution
- In hot spells, lettuce may bolt (flower) early; heat-tolerant greens and herbs cope better
Balcony Checklist
- Lidded, opaque containers with snug net cups
- Containers shaded, leaves in the sun
- Stable, wide containers for tall plants
- Check levels after storms and heat waves
