Fertilizer Concentration, Formula & Frequency

[Ray]

OK, I'm on a soapbox here about an acknowldeged pet peeve, but I think this is work stating so folks know what they're doing.

When reading through the threads here, you'll often see comments like "feed weakly" or "feed at 1/4 strength". The first is totally meaningless and the second only has meaning if you know the formula. "1/4 strength" of a 20-20-20 formula is identical to "full strength" of a 5-5-5.

Then there's the "I use {this brand}" folks, who either think the readers are clairvoyant, or don't understand that many fertilizer brands have different formulas.

Feeding frequency is also important. At the same teaspoons-per-gallon mixing ratio, feeding a 20-20-20 once provides the same nutritional level as feeding four times with a 5-5-5.

Fertilizing our plants is analogous to meal planning for us. The formula (particularly the nitrogen content) combined with the mixing concentration is the "calories in a meal", while the feeding frequency is the "number of meals to be eaten". Without considering all three, a discussion about nutrient needs is worthless.