Athosanswered grow question 6 years ago A regular sized plant needs a space of 30*30 cm; so at the very least you can put 3 or 4 more plants. You can add even more or less. The more plants, the less time you will need to veg to fill the tent; on the other hand the less plants, the more time you will have to veg to fill the tent before switching to 12/12.