As far as brilliant inventions go, hair conditioner is absolutely at the top of my list. Some of you may take this grooming aid for granted, slicking a palm full through your locks each morning without a second thought. Not me. I consider my conditioner. I have no choice. Without a dose of the goo my thick, unruly coif would tangle itself into one big dreadlock. And I like my conditioner extra viscous—and of course, as organic as possible. Healthy hair has no tolerance for synthetic colors or fragrance or artificial preservatives. These are some of my favorite ways to condition:

Oh, John Masters, I love you. I do. I’m an unabashed devotee of all that is Mr. Masters. I get my hair cut and colored at his gorgeous, eco-friendly (no stinky toxic chemical here) salon, I use his conditioner— Lavender and Avocado Intensive ($22) is particularly luscious—as well as his hair gel. The Intensive conditioner is exploding with soothing organic ingredients like avocado and lavender oils and soy protein. Your hair has never had it so good. Given the price and the effectiveness, this can be used as a once-a-week treatment.

I turn to Aubrey Organics’ Honeysuckle Rose Conditioner ($8.49) when I’m looking for a simple, reliable way to manage my do. Aubrey’s products are always free from parabens and petrochemicals and full of gentle, organic ingredients like aloe vera and jojoba oil. If you have corkscrew curls, this could be your only option.

Sometimes hair needs the extra, all-day boost of a leave-in conditioner. Enter Beauty Without Cruelty’s Revitalize Leave-In Conditioner ($10.79). In addition to being 100 percent vegetarian, the conditioner is practically an herb garden, bursting with rosemary, chamomile, sage, horsetail, nettle and lavender.

If essential oils are your thing, EO is your brand. The company’s Rose and C...