I'm at day 34 of flowering I'm using canna coco a+b canna boost and I've used pk13/14 once around day 24 since then I've been using big bud . My question is can you use pk together with big bud
The PK13/14 around here I believe is only recommended to use during the 3rd week of flower I think. I am not familiar with the exact products you are using but I would say big bud is some kind of p/k booster anyways. Just check the analysis on each pack and make sure the overall npk is something like 1/2/3 for flower cycle and be sure not to overdo the ppms. Perhaps someone with better product knowledge can help further.
It is never a good idea to mix products from various manufacturers - though I admit that many do successfully. You can get weird interactions from the "undocumented" ingredients that EVERY nutrient manufacturer uses.
For example, Big Bud is actually hydrolyzed whey protein. They use certain chemicals to stabilize this - as it has a tendency to turn funky quickly when placed into a DWC. None of this is documented on the label. What if the chemicals used to stabilize this have an effect on the other nutrients? Do you even know what chemicals are being used?
Most products that claim to provide "amino acids" are, in fact, the same thing as I drink every morning - a protein shake.
So people do it all the time... but it isn't the best idea unless you really know what is in each of the products that you are mixing.
Ill just stick to the big bud, one more thing like I said I been using big bud since week 2 an a half I'm now on week 5 could I stop with the big bud on the next feed and give it some pk13/14
Yes... I would stop. If you want to add something then I would suggest Nirvana. It is a boost of K and some other secret ingredients which seems to make a difference at this stage - haven't quite figured out what this one is as I no longer use it - I have sworn off of growth regulators.
IMO, a P boost after bloom (defined as weeks 3 - 6 of an 8 week variety) does no good. You are better off pushing K, Mg, S, and Ca at this point.
So my advice is to let it finish out with a lower P profile - it will make the smoke smoother later on. Too much phosphorus after week five will turn the ash white... which means harsh.