[dropcap class=”kp-dropcap”]I[/dropcap]t’s mid-September and time to harvest the first plant from my garden: A small Purple Pineapple. The plant is small, no bigger than two feet, with a top bud and a few small side buds. It has been growing in a 10” wide colander container filled with Hydroton (clay pebbles) in the 2’ x 8’ reservoir hydro unit in my small greenhouse.
The garden was started in mid-June. The plants all started light flowering immediately, because the 10 hours of darkness they received at the shortest night of the year (June 22) was long enough to induce flowering. With no vegetative growth period, the plants put all of their energy into the reproductive stage. This small plant took the light more seriously than its buddies. Ripeness was the result.
The other plants in the greenhouse are in various stages of flowering and will ripen by the end of the month. It’s a good time for the plants to mature. In the San Francisco Bay coastal area, where the greenhouse is located, September is one of the warmest months of the year, with clear skies rather than its famous summer fog, and with little chance of rain.
Two systems are using the same reservoir in the greenhouse. The group in the back is planted in two to four gallon containers filled with a coir-based planting mix. The mix was enriched with plant meals, which release nutrients over several months. Nylon wicks hang from the bottom holes into the reservoir. The wicks, made using 3/8” nylon rope, carry water up to the containers from the reservoir underneath. They use “capillary action” just like a tissue drawing up water. It self-regulates water uptake as needed. This action continues up the planting mix, replacing moisture as it is used by the plant and environment.
The plants also receive about a pint of water from the top four times daily using a repeating timer that is set to run every six hours for eight minutes.
The group in the front use 10” colanders just like the one used to grow the plant harvested today. They sit in about 3” of nutrient water and have a constant flow of it pumped through the hydro-pebbles. Water is pumped through the main line to the spaghetti irrigation lines directly to the top of the containers without the use of regulating emitters.
The third group consists of five plants in two-gallon containers in a 2’ x 4’ try filled with planting mix. The tray was placed against the white wall that gets five to six hours of direct sunlight daily. One of these plants will also ripen and be harvested in 10 days. The other will take two weeks longer.
Cannabis is induced to flower when the dark period reaches a critical level, which varies by variety. However, maturity can be hastened by increasing the dark period, signaling to the plant to stop flower growth and start ripening.
I decided to use this technique, starting around Aug. 20, to make sure the plants ripened a little early in September under clear skies, rather than in October, when there is always a chance of weather problems.
To do this, I devised simple light deprivation curtains that were placed over the gardens 11 hours after dawn, at about 5:45 p.m., rather than sunset at 7:25 p.m., blacking out the garden an hour and 40 minutes early. The difference in darkness was greater earlier in the cover-up, because the days were longer.
All the plants in the greenhouse are weeks way from ripening. Greenhouse receives natural light only through the roof and the front.
Wicks hanging from the containers reach into the reservoir to draw up water. This is supplemented with water pumped through spaghetti lines to the containers.
Container sitting in reservoir. In addition, water is continuously pumped through the petals. Panda plastic covers the containers creating a moist environment so the roots colonize right up to the top.
The greenhouse under wraps. The curtains go on at 5:45 p.m.and are removed shortly after sunset.
The outdoor garden. These plants will ripen in early October. They will be moved into the greenhouse after those plants are harvested when there is room.
Outdoor garden under-cover.
The Purple Pineapple is being harvested today.
Ripe bud of outdoor plant. Variety unknown.
Gelato bud has a few more weeks to reach maturity.