You can grow with a mh/hps in a 3ft space if you supercrop your plants. You can use screen of green, or tie them down to stop them reaching height. By doing this you will use up more width than height. You will still need good air circulation to avoid burning yr plants and to keep temps down. Get a heat shield which will even out your light distribution and enable you to get the light nearer the plants and choose an indica strain.

For an easy life on your first grow lowryder is an excellent starter plant as it autoflowers and only grows to about 12".

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Grow your own dope - plant a man