Grow Diary: Courgette

Verde di Milano
PREMIER SEEDS DIRECT Italian COURGETTE - Verde DI Milano - 20 Seeds...
  • Sow from late Mar under cover placing each seed edgeways 1/2in deep in well drained seed compost. Min temp 65F. Lower temperature will induce rot.
  • Harden off steadily and avoid planting outside until the soil has warmed around early Mid May in UK conditions. Protect young plants from slugs and snails.
  • Plant in a sunny protected site, with soil enriched by organic matter, 24-30in between plants. Keep well watered, fed during summer months and harvest regularly.
  • Plants will crop all summer until late Sep in frequently harvested.
  • “Soil Association” registered and certified Organic - AP22387. Professional DEFRA licenced Quality Seed Supply only - Minimal packaging - Ziplock / foillabelled bags - Instructions not attached - See details provided above for cultivation advice.
  • Test Plants: Courgette (Verde di Milano)
    Verde di Milano
  • Growth Medium: Aqua Vega - 700ppm - pH 6
  • Location: Conservatory
  • Hydroponics Setup: 10L Kratky hydroponics system

Courgette (Verde di Milano) seeds were started in a heated germinator (Garland Fab4 Electric Propagator) using Root Riot Organic Starter Cubes, with seedlings sprouting by day 4-5.  On day 7 after seed start, the seedlings were relocated to a 10L Kratky hydroponics bucket containing Aqua Vega nutrient media at a concentration of 700ppm and a pH of 6.0.  The seedlings grew quite aggressively and by day 22 after seed start, one of the plants was moved into a separate bucket containing the same concentration and pH of Aqua Vega nutrient media to try to ensure that there would be enough space and nutrients for both plants to progress as long as possible.

By day 35, lots of male flower buds could be seen on both plants, with the first flowers blooming on approximately day 41. All of the opened flowers were male, however at around the same time, flower buds with tiny courgette-like shapes behind them were also spotted on the plants - these were the female fruit-bearing flowers.  

At around the same time as the first flowers were blooming, the plant leaves started to turn yellow along their edges and the plants started to look decidedly less healthy. In addition, the first flowers that had bloomed, fell off the plants only a day or two after opening indicating that all was not well with the plants. Checking the media nutrient concentrations revealed that their levels had fallen to about 300ppm and their pH levels had fallen dramatically to pH 3.7! In addition, the media volume was lower than would likely be required to get edible produce. As a consequence, the experimental grow was terminated much earlier than expected on day 46.

In conclusion, the courgette plants are very aggressive plants which can grow very well in hydroponic systems. However, a number of changes would be needed to any future grows. These are:

  • As the plant is quite large, each plant should be grown alone away from competition with other plants
  • The 10L bucket Kratky hydroponic system is not sufficient to get any sort of fruit yield - a recycling hydroponic system would be more appropriate
  • The pH of the nutrient media (and the nutrient concentration levels) needs to be monitored and adjusted throughout the grow

Day 7

Day 15

Day 22

Day 35

Day 41

Day 45

Day 46 - the roots