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[oldstoner]

Hello all I've popped my beans glad to say they all shot up it's been a week now. What I'd like to know is how many roots should be showing before I pot up to the next cubes. 

Im doing an nft system planted in rockwool I've started the beans in tissue now I've moved them to small cubes. How long should I wait to pot up to the last and final cubes. I'm just about to give them there first bit of food a nice 1/4 strength off Cana veg and a little super thrive should I add a little rizotonic to encourage the roots along ?

 

any advice will be greatly appreciated thanks in advance