Stages 1 & 2: From unrooted to rooted cuttings
Stage 1 of propagation (from stuck cutting to callus) The first step is to decide if you’re going to use a surfactant. A surfactant works by breaking the surface tension on the leaf, which allows the cutting to rehydrate quicker. This allows every mist cycle through the duration of Stage 1 to be more effective. Most importantly, surfactants help to minimize stress on the cutting. Planning a proper mist strategy for the first stage of propagation is important to ensure success. After sticking the cutting, it can take anywhere from three to 10 days for the callus to develop, depending on the crop. The goal is to rehydrate the cuttings as quickly as possible. Maintaining a high humidity during this stage helps the cuttings stay turgid. You don’t want cuttings to dry down or wilt during the first three to five days. The ideal propagation zone should feel warm like a sauna. Soil temperature in the liners should be between 70 to 74°F (20 to 24°C), depending on the crop and location. More importantly, the soil temperature should remain above 68°F (20°C) throughout the night. The daytime temperatures should range between 68 to 80°F (20 to 27°C). You should increase humidity to maintain turgid cuttings, but not too
you could potentially leach out nutrients. If this occurs, increase nitrogen levels to 75 ppm. If nutrients are leached from the cuttings, they develop into soft, weak liners. Once the callus is formed, you can increase nitrogen levels to 75 to 100 ppm. Stage 2 of Propagation (from callus to rooting) Once the callus has started to form, we’re at Stage 2. For some crops, this can be just a few days after sticking, and for others, it could be six to eight days, so it’s important to understand when this occurs for the crops that you’re propagating because there’s action to be taken in this stage. In order to force the cutting to initiate roots, we must make it work a bit to survive, which means we start to cut back both the mist frequency and the soil moisture .
Unrooted cutting
Callused cutting
high as to cause breakdown or botrytis. Light intensity should range between 1,300 to 1,500 foot-candles. Remember – minimizing the stress on the cutting and rehydrating are crucial in the first few days of propagation. Fertility Initially, cuttings don’t require fertilizer because they don’t have developed roots uptaking nutrients. Start with low nitrogen levels around 50 ppm. If you’re using an overhead mist system,
BIGGEST MISTAKES
STAGE 1 • Allowing cuttings to dry down in the first three to five days • Over-misting • Allowing soil temperatures to drop below 68°F (20°C) • Not having the right environment (too high of light levels, too much air movement) • Not minimizing stress on the cuttings
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