Outdoor grows in Michigan have had a turbulent summer, packed with lots of rain and storms. Green house growers are likely to have weathered the storms better than some, but with the high humidity, mold issues are a challenge as well. September is when the days shorten towards the end of the month. The fall equinox lands on the twenty-third of this month, however many breeds of cannabis will start to mature and show their pistols (white hairs) as soon as mid-August. By paying careful attention to your plants and the changing seasons, you can make sure your plant finishes with optimal ripeness and avoids the tragic freezes in October and November.
September is a good month to cover your outdoor grows with translucent plastic if you have not yet done so. By law all outdoor grows must be covered on all sides and be secure on the top as well. Take caution when covering your grow area and make sure ample air flow circulates throughout. In early September, light pruning of bottom branches can stimulate flowing and help with airflow in congested grow areas.
There are many different breeds of marijuana plants, which have different flowering times. Indicas tend to have a shorter flowering cycle, typically between 7-9 weeks. Sativas usually take longer to finish, often 9-11 weeks. Hybrids, Indicas and sativas all vary, so consulting the seed producer website, to learn what they indicate is the appropriate flowering time, can give you helpful information. Outdoor growing can extend the flowering cycle a week or two due to the gradual shortening of the days.
By using a hand-held microscope, 30-100 times magnification, trichomes can be observed. The goal is to harvest when the trichomes are milky with hints of amber. Check every plant regularly throughout the month of September to get a feel for which plants to harvest first.
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| Clear trichomes indicate that it is too early to harvest this plant. |
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| Harvest when trichomes are milky with subtle hints of amber coloring. |
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| Too much amber color indicates that this plant should have been harvested sooner. |
