Revegetation in dry times - Cocoon planters

Revegetation is a tricky business when the rainfall is less than 300 mm per year. Evaporation exceeds rainfall in all months and by approximately 15-fold in January! We use a combination of direct seeding and hand-planting tube-stock. We used to wait for the “Autumn break” (the first good rains after summer) but now we plant in April, even if there’s no rain, so the plants get a good start before their first summer. We water the tube-stock throughout the first summer, applying 10-15 litres of water up to fortnightly depending on the conditions. Despite this time-consuming process, we can still have high mortality and plants are very slow to establish. (Although in 2021 we tried worm castings and the results are promising … see here).

In 2020, we trialled these Cocoon planters to see if the extra cost and time spent planting leads to better outcomes - both survival and growth rate of the tubestock. We planted Slender Cypress Pine (Callitris gracilis) in mid-September 2020, hoping that the cocoons will get them through their first summer.

And here is the step-by-step process:

December 2020 update: We’ve only had 10 mm of rain in the past two months and the 25 litre reservoir was empty by early November. They are not designed to be refilled, but with a few days over 40 degrees, I didn’t want the Pine to die. We put a little plug in the lid and refilled the reservoirs, once in November and once in December. The Pine look very healthy and are already larger than the two year-old Pines planted under conventional conditions.

A cordless drill and a hole-saw.

A hole just right for a champagne cork.

A plug so the cocoon reservoir can be refilled.

January 2021 update: We had a summer thunderstorm on 3rd January (24 mm). I noticed that the water pooled on top of the lid. If I had inserted the cork at the lowest point of the lid, it would have been easy to pull out the cork and let the cocoon reservoir fill from the rain. Next time!! Here are some photos of growth over the last four months.

First published September 2020. Updated 2021.

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Watering revegetation

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Zebra Finches and Porcupine Grass