Peter Vakomies
Member
I would skip MKP if you already have a bloom booster - they are the same thing usually.
Mono potassium phosphate - MKP - is another good dry powder to have on hand. This is all that's in every "bloom booster" out there. I use MKP sometimes but only at a rate of 0.25g/liter. Loads of more P can start to cause insolubility issues - Ca, SO4 and Fe get bound up.
Phosphorus is the most expensive nutrient, so a base-fertilizer costs a little more if its high in P. A Base fertilizer like Plant Prod 15-30-15 has heaps of extra P for enhancing blooming, and costs $10 more for a 15 kg bag. I switch to 15-30-15 as blooming starts.
When in blooming, using a base fert' like 15-30-15, or when finishing the last 2 -3 weeks of blooming with a base fert' like 8-20-30, you're ok to skip the MKP. These base fertilizers are high in all cheated micronutrients, especially iron, so switching them from veg' to bloom changes nothing but N,P,K ratios.
Potassium is rarely lacking in a typical cannabis nutrient solution; we use pH Up made from KOH and often add potassium silicate to raise pH as well. These two sources are a big boost in K, and it is important to keep the potassium high - it's the "quality nutrient"!
Most bottled fertilizer additives (the non-N,P,K ones) must contain a 5% fertilizer salt in them to be sold as a "fertilizer" and the one commonly used is potassium sulfate. So with or without all those additives, we are constantly adding more K to our reservoirs.
Also, MKP at 0.20 g / L makes a great clone-starter fertilizer, BUT remember to raise the pH - MKP solutions will be acidic!
Mono potassium phosphate - MKP - is another good dry powder to have on hand. This is all that's in every "bloom booster" out there. I use MKP sometimes but only at a rate of 0.25g/liter. Loads of more P can start to cause insolubility issues - Ca, SO4 and Fe get bound up.
Phosphorus is the most expensive nutrient, so a base-fertilizer costs a little more if its high in P. A Base fertilizer like Plant Prod 15-30-15 has heaps of extra P for enhancing blooming, and costs $10 more for a 15 kg bag. I switch to 15-30-15 as blooming starts.
When in blooming, using a base fert' like 15-30-15, or when finishing the last 2 -3 weeks of blooming with a base fert' like 8-20-30, you're ok to skip the MKP. These base fertilizers are high in all cheated micronutrients, especially iron, so switching them from veg' to bloom changes nothing but N,P,K ratios.
Potassium is rarely lacking in a typical cannabis nutrient solution; we use pH Up made from KOH and often add potassium silicate to raise pH as well. These two sources are a big boost in K, and it is important to keep the potassium high - it's the "quality nutrient"!
Most bottled fertilizer additives (the non-N,P,K ones) must contain a 5% fertilizer salt in them to be sold as a "fertilizer" and the one commonly used is potassium sulfate. So with or without all those additives, we are constantly adding more K to our reservoirs.
Also, MKP at 0.20 g / L makes a great clone-starter fertilizer, BUT remember to raise the pH - MKP solutions will be acidic!
