Effects of pH on Growth of Green Onion, Allium fistulosum, placed in soaking solutions made of Vinegar, Bleach and Tap Water


  • Gurleen Gill
  • Dilraj Josan
  • Eleanor Liu
  • Ella Shen


The use of soil culture for vegetable growth has negatively impacted the environment.
Pesticides and fertilizers used in traditional soil culture methods are proving to have detrimental
effects on surrounding biodiversity (Mahmood et al., 2016). Hydroponics, growing vegetables in
solution rather than soil, is an environmentally friendly method and a solution to these problems
(Jensen, 1999). Although growth of most vegetables has been studied through hydroponic
methods, there is a lack of research on green onion growth. Our study soaked green onion bulbs,
Allium fistulosum, in solutions of pH 3.00, 6.06, 7.07, 8.00, and 11.03 made from vinegar,
bleach, and tap water. We measured the total stalk length of green onions after each week. We
hypothesized a slightly acidic environment to be the optimal pH for green onion growth. The
results showed that pH 6.06, 7.07, and 8.00 had no statistically significant difference in green
onion growth. However, the tests also tell us that soaking solutions of pH 6.06, 7.07, and 8.00
treatment groups did have statistically different results from the pH 3.00 and 11.00 treatments.
While we could not identify the specific optimal pH, we found that generally neutral solutions
with a range of pH 6.06-8.00 provided optimal growth for green onions compared to highly
acidic or basic solutions.