Growing marijuana in Hawaii

I live in Hawaii which is a great place for marijuana plants throughout the entire year. Of course, the island has somewhat strange seasons. There is a long season that extends from April to September (or longer) and then a continuous short season all the way through to the end of March. At what time should I plant my marijuana seeds and what are some ideal varieties?

You have plenty of options here. During the short season, you can grow marijuana strains like sativas, sativa-indica hybrids, and indicas. Sativas come from areas on earth that are close to the equator and are acclimated to little or no variation in the length of the day. They do, however, respond to dark periods that are larger than 12 hours. The marijuana plants will continue to grow as they flower. Once the days get shorter and they attain a height of 3 to 4 feet, more of their energy goes into flowering. Sativas that come from higher latitudes like Mexico or Jamaica will also flower as they grow but reach maturity earlier.

Sativa-indica hybrids maintain differences in the way they respond to darkness. Marijuana plants in the mid-range (e.g. indica-sativa F1 hybrids) get half their genes from each parent. They continue to flower as long as the dark period stays over 11 hours daily. After about the first half of April, the plants will stop flowering and begin vegetative growth once again. Occasionally, some flowers might pop up, but they will not flower in earnest until the beginning of fall. When their flowers have ripened, they can be coaxed back into vegetative growth by interrupting the dark cycle every night using a bright, incandescent flashlight. It needs to be shined on every branch several hours after darkness has fallen. When the marijuana plant attains the right size, it can be induced to flower again so long as the period of darkness is 12 hours or more.

Indicas originally came to us from Afghanistan and the adjacent nations in the Himalayas. Like most of the hash-producing areas, this region is right at the 30th parallel. These plants start flowering when the period of darkness is around 10 hours (late July in Afghanistan). Once they are placed outside in the short season, they will start flowering and stop growing. The buds might be somewhat small because the plant ripens so fast under long-night conditions. Some Hawaiian marijuana growers have been known to use a light system to make sure the plants get to the right size. Then they take them outside to ripen.

It is still feasibly to get quality buds during the long season even if Hawaii is at the 15thparallel. Even during the peak of summer hours (June 22) Hawaii still gets 10 or more hours of darkness. Indicas planted outdoors just prior to that peak will have a chance to grow before the long night induce flowering. They will ripen in late August to early September. During the long season, most sativas stay in vegetative growth. They will not start flowering until late September and will ripen about 8 to 10 weeks after that. Certain sativas can actually grow to be very big marijuana plants. Hawaii provides an environment conducive to optimal plant size. Sativas normally grown in more northern regions will start flowering in mid-July and will start ripening by the beginning of September as a result of Hawaii’s short daylight hours. Mid-range sativa-indica hybrids will start flowering at the end of August all the way through to the end of September and will ripen about 6 to 8 weeks later in October and November.

You can plant all of these varieties in late summer to reduce their size and exposure to peril. Many indoor varieties, particularly fast-ripening ones, are largely indica that have been acclimated to lower light levels provided by indoor cultivation. These marijuana plants will still grow bud when partly shaded from the tropical sun.


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This is excellent, you could not have explained it better!

This also follows the thought that Sativa strains can be grown in 12/12 photo period from start to finish. I still think Sativa originated in the equatorial regions, but there has been some debate about that recently.

It has nothing to do with where cannabis originated, but yes sativas have been bred in equatorial regions long enough that they now grow this way. It’s like saying Polar bears originated in the arctic and that is why the are white, no, they originated much further south as Kodiak/grizzly bears but lived in the arctic long enough for their hair to turn white. Where an organism originated from doesn’t mean much of anything, all vertebrates originated in the ocean but land animals don’t have gills anymore.

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I live in Jamaica on 18° N, I am mainly interested in growing Sativas and in the near future also CBD strains. Should i just germinate them under a dome outside and then put them in the sunlight, no extra hours of light added with CFL’s? does this mean my plants will go from seedlings (10-15cm long) straight into flowering but will still keep growing to like maybe 50cm-100cm when completely finished? I am growing right now outside from seeds and have them veg for almost 2 months now, i use CFL lights from 6pm until midnight and its turned off (dark hours) between midnight and 6am. Advise is welcome, its my first grow ever, and all these conditions are new to me (i grew up in the netherlands).


Here you can check the hours of sunlight for Hawaii - Sun & moon times today, Honolulu, Hawaii, USA I use this and then calculate my additional lighting schedule to make sure I’m always hitting 18 hours of light for my vegging plants.

Thank you so much!! I am new and know the post is super old but I was cruisin lookin for some info here and ran across this.
Thanks again
And happy gardening