pH Cycle
March, 2002

A hydroponics cycle conducted from Oct 6, 2001 to March 6, 2002 intended to explore using worm bed drainage as nutrient solution for an extended period of time, to seed production in the hydroponics plants. The basement lab had an average 67° F temperature and 78% humidity.

Acid pH 5.5

In that the worm beds had been fed during the summer of 2001 with manure the drainage was rich and promptly moved within a few days from a pH of 6.5 to a pH of 5.5. The pH was balanced with wood ash water, i.e. water left to soak in wood ashes for a few days, then drained from the top as a clear alkaline water and added to the hydroponics reservoir. This was added every couple weeks, a couple quarts of wood ash water to the 80 gallon reservoir. This balanced the pH back up to 6.5 and even 7.0.

 

Alkaline pH 7.5

After running 4 months with adequate Nitrogen, 10 gallons of worm nutrient solution which had been set aside was added to the hydroponics reservoir. This had been covered, protected from light, so retained its nutrient value in suspended particles and bacteria ready to break down the particles. In anticipation of a high acid reaction, wood ash was added in the same proportion as earlier in the cycle, but this caused the pH to go alkaline to 7.5, yet another shock to the plants. Apparently, stored the nutrient solution does not have the acid pH potential of fresh solution.

 

Plant Shock

The early 5.5 acid pH caused the sprouted seedlings to falter and wither or the seeds to fail to sprout and eventually molder. After the pH was balanced to 6.5 new seeds planted then sprouted and existing plants rallied. However, since early growth had been stricken, these existing plants were runts and never recovered from their failure to grow during their early growth spurt period. The shock of having a 7.5 pH later in the cycle also affected some of the plants.