I don't know if this is the answer you want. I use Ortho RosePride Flower & Rose Care (8-12-4) on my amaryllis once a month. Since they are planted outside next to the rose bed it is easier that way.

For the ones I have in the pots right now I use Jobes fertilzer spikes (10-10-4). It depends on the size of the pot how many I use. Come spring I will plant them outside.

I am sure others on this forum witll disagree with what I do, but with 2.5 acres to take care of year around here in California I have to use easy and quick methods. I aint as young as I use to be!

The potassium content is far too low in comparison to the other macronutrients.

I read here somewhere to use Miracle Gro. I bought a full box in Costco and was using it last year. I plan to fertilize with it in the flower bed as well. It has a low middle number.

I agree with Hans.
I am using simple ratio 2-1-3'

Hi Guys:
I use Rose fertilizer, do not need 15 different types
of the stuff to do different types of plants. I do use
10 52 10 for starter plants and use full strenght for the roses and dilute it for the Amaryllis.
So far they aint complaining, and like aptosca I aint gettin
any younger either .LOL
One plant has 2 bulblets on the main bulb, which languished
in a small pot for a year, Thanks to Hans they now have
combined 12 leaves total in a 12 inch pot. Happy
Mothers Day...... Jack