Next Step: Fruiting Plants
Lesson 13 of 14
Once you have harvested a few greens, fruiting plants are the natural next challenge. The method is the same, but everything is bigger and slower.
What changes with fruiting plants
- Bigger containers. A tomato or pepper drinks far more than a lettuce, and fruiting crops usually need the solution replenished over time (UC ANR). Use a bucket or tote holding several gallons, kept dark like any Kratky container.
- Topping up. These plants grow for months, so they will need topping up. Follow Lesson 10: add solution only to the lower roots and keep the air gap.
- Stronger solution. Oklahoma State University Extension lists an EC range of 2.0–4.0 mS/cm for hydroponic tomatoes, compared with 1.2–1.8 for lettuce. Many growers use a nutrient with more potassium once plants flower.
- Support. Stake or cage the plant so its weight does not tip the container.
Start with dwarf varieties
Micro-dwarf tomatoes, like the ones in our garden photo above, stay small enough for a large jar or small tub and are a good bridge from greens to full-size plants.
Pollinating indoors
Tomato and pepper flowers pollinate themselves, but they need movement to release pollen. Outdoors, wind and insects provide it. Indoors, gently shake the flowering stems or tap the flowers every day or two once they open.
Pruning
Removing some side shoots on vining tomatoes keeps the plant manageable in a container. Bush and dwarf types need little pruning.
Where to go from here
You have now covered the whole Kratky method. If you want one more fruiting crop to try, Lesson 14 covers strawberries. Keep notes on every crop, try one new plant at a time, and use the blog for deeper questions.
Related Articles
- Pollinating in a Hydroponic Space: Tips for Successful Plant Propagation
- How to Trim Tomato Plants for Max Bloom
- Catch Up on Growing Tomatoes with Hydroponics
Sources
- Dunn, B. and Singh, H. Oklahoma State University Extension. Electrical Conductivity and pH Guide for Hydroponics (HLA-6722).
- UC Master Gardeners of Orange County, UC ANR. Kratky Hydroponics: Soil-Free Growing Method.