17-2-7 is way out of balance for weed (I aim for a 1:3:2 ratio throughout my grow adding some nitrogen to the ones in veg) so my NPK values using that stuff would want to be 17-51-34, especially during flower, and then id use it very sparingly. The number is how much in weight per x it contains, so that stuff has very little in the way of phosphor or potassium. You could supplement it, see if you can get some PK 13/14 and maybe a mix for trace elements. I would import some salts if you have to, Potassium sulphate and ammonium dihydrogen Phosphpate, I got some food grade stuff kicking about, was easy enough to order online
Be careful with it the nitrates do most of the damage when things are in high enough levels to be toxic, when you have too much phosphor or potassium it generally blocks absorption of itself, so you will get a deficiency, but nitrogen burns where the water evaporates, think of it like an engine, if your fuel mix is too rich your exhaust backfires as excess fuel is burnt elsewhere, the plants leaf tips are where the plants water vapors collect, nitrates will kill the cells and you will see brown on the tip of the top leaves. Generally when I see brown tips i know im pushing too much light for the condition in the roots (too much nitrogen), the harder you push the more it will sweat and more of the leaf will go brown and die, so take the burn as a warning if you see it. If your leaf tips lighten slightly its a sign they are drinking back their own moisture, if there is no burn that is a general sign you are pushing them nice and hard with things nicely balanced on nitrates at least
When its hot like that 32c you want to be careful, you can't really control the overall VPD of the plant but you can do things to aid it. VPD charts will want it humid, like 60%+, they will help you keep out of trouble if you take the time to understand its relationship to the plant
VPD is an indicator on how easily the plant wants to dump its moisture at the leaves, while its working in a well lit environment. The dumping of the water lets more water come up the plant, the warmer it is the less viscous water acts in the veins, the lower the humidity the easier the water exits the plant, Your plant makes and spends sugars to drink via the light hitting the leaves, all of this works as a balance
If you can't control the temperature or humidity you can move the plant to a more shaded spot, as long as there is light enough for it to work it will be happy to just chill out on those stressful days, There is a point where you can have too much water and nutrients flowing inside the plant. It is a pumpless system so the bigger your deltas the more free work you get (higher temperatures and lower humidity = free energy for your plant), in theory you dont need the plant to be in such a well lit area as the water wants to come in and out of the plant easier, if it can save 50% energy in drinking it could live and do good things with say 30% less light, it doesn't need to make the sugars to drink to get all those nutrients it needs, it gets given them almost for free. If you can spray the area around the plant you can raise the humidity in that area, as the water evaporates it will cool the area down and add moisture to the air, helping the plant cope, Try not to push it to do hard work when its up like that, too much work and the leaf can't get enough water to keep up and it will just die. You would be sweating your ass off if you was to do your daily work in the sun, imagine if your eyes were burning with nitrogen, it seems like a good idea until you try it for yourself, plants are no different except they can't move, you wanna be kind give them a break when its a beast of a day ;)
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