“The only way to achieve high quality, uniform crops is to start with high quality, uniform seedlings,” said Joe Swartz, vice president, AmHydro. As moderator of the “Hydroponic Seedling Propagation” Indoor Ag-Conversations webinar hosted by Indoor Ag-Con summer, Joe and panelists John Jackson, SIGS, Nick Green, Nick Greens Grow Team and Dr. Vijay Rapaka, Smithers-Oasis, took a deep dive into the topic, sharing a wide range of tips and innovations with the audience.
During the program, Dr. Rapaka, Ph.D., Corporate Research Manager, Smithers-Oasis, zeroed in on 5 critical tips for propagation success — regardless of the type of growing system you’re using:
We know light is important for photosynthesis. It is also key for photomorphogenesis (the development of form and structure in plants which is affected by light). Once the seed cracks, he says, you need to focus on proper light intensity and light duration. You cannot ignore one or the other. Otherwise you will end up with a number of issues. These can range from elongation to yellowing leaves suffering from lack of chlorophyll development.
Frequency and duration are key, says Rapaka, whether you are running a multi-million-dollar facility controlled with a Priva system or a smaller operation using a Rainbird control system. Since most of us are growing crops like leafy greens and tomato seedlings rather than rice, you only need to water once a day or every other day. You do not have to bombard or flood your plants multiple times a day. The plant quality suffers because the roots can get excess water, which is not good for seedling growth.
To be clear, Rapaka is separating watering from nutrients. He disagrees with old hydroponics textbooks that suggest nutrients are not required until day 3 or 4. When growing crops in controlled environments where, for example, you’re providing light and CO2, if you do not have the right nutrients, you’re headed for trouble. You do not have to put the plants on a restricted diet he says, using human gluten free diets as an example. But, as soon as the seed cracks, he adds, it needs to see nutrients. Regardless of the media you’re using, make sure you are treating with nutrients starting with the very first watering.
Sometimes people think if they’re planting really high density, they can go with a smaller footprint or smaller plug size to save a few cents. Rapaka explains that you will lose dollars in the long run here because once leaves start emerging, there should be no shading effect. If there is, propagation quality suffers.
Turns out, timing is, indeed, everything. You have to do the right things at the right time, Rapaka explains. It’s wonderful to grow beautiful, quality seedlings, but it’s critical to transplant them at the right time. If plants get overcrowded or rootbound, you have a transplant delay. Whatever quality you are achieving at the young plant stage will not be transferred once you transplant.
During his presentation, Rapaka also shared updates about Fortify, Smithers-Oasis’ new liquid nutrient supplement, designed to optimize the growth performance and increase harvest weights while reducing production time by up to 20%.
In short, said Rapaka, hydroponic production is sexy, propagation is not … and it is often neglected. Everything starts with propagation. You’ve got to start strong to end strong, he adds.
The entire webinar, as well as many others in our new Indoor Ag-Conversations series, are available on demand. Simply visit our Indoor Ag-Conversations page to access the recording.