Yeah they look healthy, you would start having your leaves turning yellow if you were doing something wrong as far as the soil goes. I found with cannabis less is more, they're pretty resilient and don't need a lot of water. Just don't let the soil get too dry, you would notice the leaves starting to really droop downwards.
Now your setup is not going to produce as much product as let's say something very powerful like a 1000 or 600 watt metal halide setup, and cutting vegetation short will cut down on yields as well but that won't effect the health of the plant. If you think your soil needs replenishing you can always add in a small amount of beneficial bacteria blasts such as "Recharge" by Realgrowers or this really great product I liked called "Oregonism XL" by Auroa; free of synthetic fertilizer. However in the last two weeks of growth, give them nothing but water to flush out the soil. Another point, to prevent mold in the final stages of flowering keep humidity levels under 60%.
Honestly though you have nothing to worry about if you're keeping an eye on them every day, good air movement from fans blowing on them. Now that they are in the flowering stage, if you notice any male duds just pull em out before they cross polinate with the females; if not you'll get seeds in your product like the old Mexican brick weed. You'll notice males by their pollen sacks instead of white hairs, and once you start seeing seeds in your product it is too late.
Don't harvest your product until a good majority of the hairs have turned brown. Don't blow a fan directly onto your harvested material, and keep it in darkness as much as possible as it is drying. After about a week of drying you're good to place in an airtight jar, wait any longer out of an airtight container and the outside of the bud will become too brittle which doesn't make a good product to smoke; a properly cured product is a must.
