Deadly potion

I’m very new to growing. I started three healthy plants (two 12″, one 22″) in a simple hydro setup consisting of a drip system draining back to a tub filled with water and hydro nutrients. The plants are in meshed pots with lava rocks and perlite. The plants were all doing great until I followed a friend’s advice and added a cup of blood meal to each tank.
I was devastated when I entered the garden the next day. The two smaller plants were wilting. Their roots were covered in a muddy material generated by the bloodmeal. Then the roots fell out. Now the plants are barely alive. I flushed out the tubs and refilled them with the nutrients I had been using.

Do you have any suggestions on how to salvage the two plants that are almost dead? How about recommending a good hydro solution that can be used in this type of growing environment?

Kiltboy, Texas

Blood meal is not a good fertilizer to use in a recycling hydroponic system. There are several reasons for this. The first is that it is hard to measure the water/nutrient strength because instruments that rely on the electrical conductivity of soluble salts ? PPM meters (parts per million) and EC meters (Electrical Conductivity ) ? do not measure the dissolved nutrients that are not salts.

Most chemical fertilizers are present as “salts,” chemical compounds that contain the nutrient element. For instance nitrogen is usually in a nitrate (NO3 or nitrite (NO4) These have electrical charges that affect water measurements. Organic fertilizers may contain some nitrogen bound up in organic form that is insoluble and is released gradually. Other forms of the nitrogen in organic fertilizers may be soluble but not carry much of an electrical charge. Meters are unable to measure these last two forms of nitrogen.

The second reason for not using blood meal or other organic fertilizers such as fish emulsion or compost tea in reservoir systems is that colonizing microorganisms quickly attack the nutrients. As a result the water/nutrient solution rots or ferments and becomes unsuitable for use as a hydroponic solution.

Your plants wilted after one day because the solution was too strong and drew water from the leaves out the roots. You followed the right course of action when you quickly replaced the blood meal with the solution you had been using. Hopefully your plants will recover soon.

You have already switched back to the original fertilizer. That was a smart decision. You were satisfied with its results. Now don’t switch to a different product halfway through the project again.

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