Here is an update regarding the “Benefits of Castings & Leachate” experiment. And it has been a rough ride so far. At the start of the experiment it was still relative cold, with some freezing conditions in the night, and I decided to keep the experiment in a small cabin at the edge of a forest that borders my garden. A few days into the experiment the weather conditions changed a lot. We experienced the hottest Easter in decades, with temperatures reaching 28 degrees C (82.4 F). Early on this was good as it caused the seeds to germinate relative fast.
The first seedlings were observed on T6 (6th day after the start of the experiment). Pictures were taken each day to see if we could observe differences in germination rate. I’ll try to analyse this data soon and provide an update regarding that.
Figure 1: First observation of the germinating seedlings.
On T10 it became clear to me that the weather caught me off guard. The trees near the cabin started to open up their buds and carry leaves, blocking most of the sunlight to the cabin. Seedings start to react to this in a process called “etiolation”, and the high temperatures only made it worse. Etiolation causes the “embryonic stem” (hypocotyl) to stretch and become weak, and as a result the seedlings start to fall over, often breaking their hypocotyl.
To prevent this from worsening, I transferred the seedlings outside. As the seedlings were fragile already, I knew they would not be able to handle the full sun, so I put them in the shade of a hedge. In the evening I checked on them again and they were doing a lot worse. I decided to keep them in that spot and see if they would recover during the night.
The next morning (T12) I took the final pictures for the germination part of the experiment, but it was clear the experiment might be coming to an end. I decided to keep the plants in that spot, and spent some time thinking about how I might salvage the remaining seedlings to keep at least a part of the experiment running.
In the afternoon I noticed the sun was shining onto the seedlings, helping to explain why their conditions had worsened the day before. The sun was getting higher during the afternoon, causing the seedlings to be exposed to full sun for a few hours. I quickly moved them to a spot in full shade.
The next day (T13) I moved them back to the forest cabin and checked on the survival rate.
Figure 2: Too much sun exposure to the fragile seedlings.
In the normal garden soil 9 plants survived, in the potting soil 3 plants survived, in the castings mix 6 plants survived, and in the potting soil mix all the seedlings died.
I tried to keep the experiment as close to the original plan as possible, but naturally I’ve had to make some adjustments. I switched to only one seedling per pot, so I had to transplant some. And for each soil class I have 4 plants (garden soil and castings mix) or 3 plants (potting soil and garden leachate soil). Although the soils still had some water in them, I added 5 ml of tap water (garden soil, castings mix and potting soil) or 5 ml of leachate (1:9 dil.) to the soil next to the seedling.
Here is a picture of the current situation:
Figure 3: Replanted seedlings for the redesigned experiment.
There is cooler weather with a bit more rain on the way, so I hope this will be sufficient for the seedlings to become more resillient to weather extremes.
I will keep everyone posted on my progress.
About the Author
My name is Myckel Habets from the Netherlands and for the past decade I’ve worked as a plant biologist at Leiden University. There I investigate developmental-related aspects of plant growth, on a molecular and cellular level. Last year I moved to a new house, with a large garden and obtained my first wormery. During the time since starting this system I’ve learned a lot about how to handle my worms properly, mostly due to the hot summer of 2018. My interests are plants and things related to them in a broad sense, computers and software development, small scale experiments and crowdfunding local entrepreneurs.