Is it a phosphorous deficiency?

My plants are starting to turn yellow and slightly brown at the tips and there curling. Is it a phosphorus deficiency or is it the hot sun?

If you post pics people will be able to do a better check up.

iloveit said:

If you post pics people will be able to do a better check up.

Click to expand...

Sorry Im having problems. Get back to you in a sec.

you should've posted under plant problems, but that's just me. you would've gotten more response. please post your pics.