You actually want to keep giving them veg nutes for the first 10 days of lower. Personally what i do is after the first 10 days of flower i start topping up my res with bloom nutes instead of veg until ive added back the same volume as my res, so i keep 50 gallons in it so i start topping it up with bloom nutes until i have added about 50 gallons to it (takes about 2 weeks) By this time the res has now been completely replaced with bloom nutes and its now time for a res change, so now i change the res and add my full bloom nutes plus i start adding half strength PK boosters now too. Then 2 weeks later i increase the PK booster strength by adding more to the res. Then after another 2 weeks i start adding more potassium and less phosphorus to swell and harden the buds and i keep using this "ripening" res until the 2nd last week of flower. I do not flush. For the 2nd last week of flower i drop my ppm to about 300 and then they get 0ppm ice cold RO water for the last 3 days before harvest. If you flush for the last 2 weeks you are sacrificing up to 30% yield. The idea of flushing is bro science. It started from black market growers who didnt know science and didnt understand plants. They excessively over fed the plants (believing more nutes =more weed) so that when it came time to harvest they needed to give the plants 2 weeks to eat up all the extra shit they were giving them. But if you dont over feed and then you drop your ppm for the 2nd last week and give plain water for the last 3 days, you get clean white ash and beautiful smoke. Instead of starving the plant for the last 2 weeks, which is fucking stupid (sorry, but it is) you feed it just slight less than it needs to stay healthy, that way it isnt starving but it is also eating any mobile nutes left over in the plant tissues. Ain water for the last 3 days is sufficient. Think about it logically and take calcium for example. Calcium is an immobile nutrient once the plant eats it, the calcium becomes part of the cell walls. No amount of flushing is going to flush out THE CELL WALLS. Its the same as saying you got too much of a sunburn so drink lots and lots of water and it will flush the UV light out of your skin cells. NO! Just fucking NO! Sorry about that, im better now. I just really want to bring science to our industry after so long of nothing but urban legend, grower stories, and assumptions. There were a lot of things us legacy growers got wrong simply because we didnt know any better and researching this field was very risky in the 90s considering that whenever a weed grower tried to buy actual horticultural equipment or get soil/nutes/weed tested at a lab, they would take our money and then call the cops
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