Sativas have long, narrow leaves. They triple in height or more during flowering, are wispy type plants and take upwards of 120 days of flowering to finish. Indicas have broad leaves, grow squat and bushy, double in height during flowering and can finish in as little as 45 days of flowering. Most folks grow varieties of Indica/Sativa crosses. Sativas give an up, exciting head high and Indicas give more of a body high, sleepy, couch-lock. So, the combination (crosses) give (hopefully) a combination of the two and a plant that finishes in 60 - 70 days.
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