I'm surprised you haven't received any replies. I've read that fertilizers with a high middle number will result in more blooms. I use Green Thumb Blossom Bloom 10-50-10, but I've read in this forum that fertizers in a ratio of 3-1-2 are better. I can't say which is better, since I've always used 10-50-10. Maybe others will have better advice.

You can't 'force' a plant to take up more phosphorous than it needs, and then to allocate that extra phosphorous toward producing more blooms. A plant uses nutrients in a particular ratio that doesn't change appreciably during the growth cycle, and plants use nutrients in surprisingly close to the same ratio. On average, plants use about 6X as much N as P, so while there could be the occasional case where a bloom booster might be shown as appropriate for plants growing in the ground by way of a soil test, it's going to be extremely difficult to explain why any plant needs a supply of P that is greater than the supply of N when the plants are containerized. Remember, that an excess of a nutrient has no potential to be a benefit, it has only the same potential to limit as a deficiency. Based on the fact that plants, on average, use about 6X more N than P, even 1:1:1 ratio fertilizers liker 20-20-20 supply more than 2.5X more P than the plant can/will use in relationship to N usage. N, because it is used more than any other nutrient, is the yardstick by which the usage of the other nutrients are measured in establishing nutritional supplementation regimens.

Excess P also unnecessarily raises pH, unnecessarily contributes to the EC of and TDS in the soil solution, very frequently causes chlorosis by interfering with Fe uptake in particular, but also inhibits uptake of K, Ca, Cu, Mg, and Z. IOW, you don't WANT an unnecessary excess of P in your soils if you can help it. Often, the grower notes the chlorosis caused by excess P as a fertilizer deficiency, supplies more fertilizer, and adds to the already existing P overload.

Your plants will grow best in containers if you concentrate on making all the essential nutrients plants normally take from the soil available at all times in the ratio at which the plant uses those nutrients and at a concentration high enough to ensure there are no deficiencies yet low enough to ensure the plant doesn't have difficulty taking up water and the nutrients dissolved in water. That's the longest sentence I've ever written that didn't require punctuation other than a period. ;-)

3:1:2 ratio (ratios are different than NPK %s) fertilizers didn't come by their ratio by accident. They come closer to supplying the '6x as much N as P and not quite 3/5 as much K as N' than any other commonly found fertilizer ratio, which is why virtually every synthetic fertilizer manufacturer markets a 3:1:2 ratio fertilizer, very often as an 'all-purpose' supplement.

If you want to arm yourself with a good understanding of nutritional supplementation and then branch out into tweaking your plants nutritional supplementation, by all means, do so; but keep in mind that 'tweaking' is a whole lot different than the wholesale supply of nutrients several times in excess of what's required for normal growth.

No matter how hard you try, you cannot make a plant grow at beyond what is normal for the plant. Your plants are genetically encoded to grow to a given potential. Nothing you can do will make them grow at beyond that potential - you can only limit their potential through ill-considered decisions and/or an inability to provide ideal conditions. That's not a censorious observation, rather, it's a reality every one of us deals with for every plant we ever have or ever will grow. The key is to eliminate to the greatest degree possible, all things that limit the plant so the plant can do its stuff w/o our encumbering it.

It's much more effective (and healthier for the plant) if you learn to manipulate bloom profusion via reducing the N supply than by over-supplying P, but that would be best left until you understand how to properly manage the manipulation. If we make a healthy plant our ultimate goal and get good at it, there would be very few of us not perfectly happy with the fruits of our endeavors, including bloom profusion.

Al

AL, I guess you didn't ream my question or maybe I didn't make my self clear. I ask if it would be OK to use the bloom builder on my plumerias after they set leaves, all I needed was a yes or no, I'm not really that dump about growing plants but plumerias are new to me, but like all the other forums on garden web there are those who like to talk down to newbe, so I guess I won't be coming back to this forum any more.
Bear

Hi Bear,

You have mail!!!

Welcome to the forum...

Take care,

Laura

Wow. The obvious answer to your question is, it's ok to use whatever you want whenever you want on any plant you own ...... because they are YOUR plants. I didn't think that would be appropriate or helpful; so instead I spent a fair amount of time explaining to not only you, but to anyone else that might have interest in the topic why the high-P fertilizers don't deliver what they promise. Talking down to you was the last thing on my mind, and if you actually knew me, you'd understand that I would have taken as much time as necessary to help you get more from your growing experience and to explain things to anyone who wants/needs/asks for help. I thought you obviously needed help because of the question you asked, and I still reason that if you already knew the things I offered, you wouldn't have asked the question.

Good luck, Bear.

Al