Need advice on orchid fertilizer

[sushiboy]

After months of waiting, my phal bellina has decided to produce a bud at the end of an existing spike. Think it either was resting from previous flowerings (can't take credits for those flowers.) or it wasn't getting enough sun until now. Now with a bud forming, i would need advice on the fert to use. I have 3 types and npk are as follows:

1) 15-45-15
2) 7-13-34
3) 21-21-21

Which one should i use? Thanks in advance.

[PurpleLotus]

NPK:

N = Nitrogen: helps plant foliage to grow strong.

P = Phosphorous: helps roots and flowers grow and develop.

K = Potassium (Potash): is important for overall plant health.

I recommend use 15-45-15 as bloom booster

[orchid-man]

I would not bother changing - use the 21/21/21 all year round