5 Tips for Plant Nutrition

Nutrient imbalances can limit yield and quality in commercial cannabis production. Here, CEA Consultancy’s Robert Eddy and Cultivation Sector Consulting’s Jennifer Martin share five tips for keeping crops healthy and avoiding these imbalances in plants, from altering root substrate to testing leaf tissue to monitor minerals.

From Robert Eddy, Consultant, CEA Consultancy

1. Incorporate porous ceramic granules into your root substrate.

Adding porous ceramic granules—sold for golf greens and athletic fields—into your root substrate at a rate of 25 percent to 50 percent by volume can improve iron uptake and cation exchange capacity, Eddy says. Though made of clay, the kiln-fired granules do not break down, but improve drainage and longevity of the substrate.

Porous ceramic can improve iron uptake, cation exchange capacity, drainage and the longevity of the substrate. Photo courtesy of Robert Eddy.

2. Install EC and pH probes in plumbing pipes to monitor and control liquid fertilizer.

For the best monitoring and control of liquid feed fertilizer, electrical conductivity (EC) and pH probes can be installed in the plumbing pipes delivering the solution, or in the reservoirs of closed loop systems, Eddy says. The probes are used for automatic adjustment of the feed, for logging data which improves troubleshooting and for alarming managers when measurements are out of proper range.

Two EC and pH probes are installed for redundancy. Photo courtesy of Robert Eddy.

From Jennifer Martin, Founder, Cultivation Sector Consulting

3. Understand that nutrient imbalance quite often causes reduced quality and yields.

Besides pests and diseases, nutrient imbalance is the most likely cause of reduced flower quality and yields, Martin says. Cultivators should keep this in mind and understand how to spot nutrient imbalances, differentiating them from other common problems like pests and diseases.

4. Be critical when selecting fertilizers.

Growers should not assume that pre-mixed fertilizers contain the right mineral balance for their plants, Martin says. Cultivators should be critical when researching and ultimately choosing the best fertilizers for their crop.

5. Test leaf tissue regularly to monitor minerals.

Cultivators should use a laboratory for leaf tissue testing every one to two weeks throughout a plant’s life cycle to monitor the uptake patterns of the 13 essential minerals, Martin says. This can help growers catch nutrient imbalances early and implement changes to correct the problem.

Editor’s Note: Robert Eddy and Jennifer Martin will be speaking at the Cannabis 2018 Cultivation Conference on “Food for Thought: Plant Nutrition.” The seminar will cover a discussion of organic and mineral-based nutrients, appropriate quantities and ratios of essential minerals, and some of the common and potentially catastrophic misunderstandings and pitfalls associated with using and combining marijuana nutrients and additives. For more information, visit www.cannabiscultivationconference.com.

Top image: © Brent | Adobe Stock