The Effects of Varying Water pH on the Growth Rate of Green Onions


  • Gurkaran Bhandal
  • Andrew Wong
  • Kellan Woo
  • Jennifer Yu


With the human population continuing to rise, so has the demand for food. Hydroponics
is an alternative agricultural practice that may provide a new and potentially environmentally
favourable way to grow crops. In this study, we examined the influence of pH on the growth of
green onions grown using hydroponics. Growth was based on the percent change in mass and a
total of 32 green onion stems were used in 4 different pH ranges: 5.5-5.8, 6.4-6.7, 7.0-7.3, and
7.5-7.8. Since previous literature had postulated that a pH of 6.5 yields the highest growth, we
hypothesized that the green onions grown in the pH range 6.4-6.7 would have the most growth
and highest percent change in mass. In contrast, our results show that there was no significant
difference between the percent change in green onion mass of the four different pH conditions
(df = 3, F-value = 0.4506, p-value = 0.7189). However we suggest that our non-significant
results could be indicative of low sample sizes and/or errors in sample weighing; furthermore,
followup studies may reveal significant results congruent with previous implications.