Empressive Farmer Ep. #3: Cover Crops and Empress Splendor Trees
Research overwhelming shows that planting the appropriate cover crops between rows of trees can yield many benefits for both the trees and the surrounding ecosystem. They can successfully suppress weeds, increase soil health, retain moisture, prevent erosion, and improve biodiversity.
They can even provide nourishment for honeybees, ladybugs, other pollinating insects, and foraging livestock.
World Tree was pleased to be joined by Dr. Ramdas Kanissery, Assistant Professor and Weed Scientist from the University of Florida, for this special webinar on the topic of cover crops. Dr. Kanissery’s research is primarily with citrus crops in Southwestern Florida, with growing regimes similar to those of World Tree’s Empress Splendor (Paulownia) trees in the Southeastern US. Under both systems, trees are planted in rows with considerable spacing, the rows are kept weed-free, the trees require periodic irrigation, and some vegetation can be maintained between the rows.
Not to be confused with intercropping, the definition of a cover crop is one that is grown for the primary purpose of enriching the soil and other benefits, not as a cash crop.
Dr. Kanissery emphasized that planting cover crops for purposes of weed suppression can be difficult, as anything you do to encourage the trees to grow will also encourage the weeds. Weeds compete for light, nutrients, moisture, and space, and impact the growth and health of the tree and cover crops. Weeds can also attract deadly pests. It’s therefore imperative that the correct cover crops are selected for optimal benefit.

Examples of cover crops that can be tried:
- Ryegrass and oats (also good for grazing)
- Daikon grass (fast-growing, edible, big roots)
- Buckwheat (supports pollinators)
- Sunn Hemp (lots of biomass)
- Cowpea (legumous nitrogen fixers)
- Crimson clover (leguminous and supporters pollinators)
Some other things to keep in mind:
- Set goals to determine what kind of cover crops and when to plant them, because different cover crops accomplish different tasks.
- Understand the different factors that will impact how you need to establish your cover crops – for example, seeding rate, herbicide carry-over effect, and soil moisture.
- Plan for timely termination of the cover crops – too much is not desirable.
Dr. Kanissery also encourages us to be patient! It takes time and experimentation to get it right.
You can reach Dr. Kanissery at the University of Florida, Southwest Research and Education Center