Good and Bad News

So…I have good and bad news today.

Let’s get the bad news out of the way first. We’ve been running into some small but noticeable issues with growth across all of our test plants. After a bit of digging (no pun intended), we think we’ve figured out the root cause: an oversight during soil sterilization. When we autoclaved our soil, we didn’t account for how that would impact its water retention.

Soil retention is in part determined by something called soil aggregates — clumps of soil held together by organic matter, microorganisms, and a few other minor factors. When we autoclave, we’re basically pressure-cooking the soil. It’s meant to kill off bacteria using high heat and steam, and we bag up the soil before putting it in. But this process also evaporates all the moisture, breaks apart organic matter, and wipes out the microbes that help maintain those aggregates. What we’re left with is dense, compacted soil that holds onto water way more than it should.

At the start of the experiment, we were watering each plant with 20 mL daily. Things looked great for the first few days — but then growth started to slow. Turns out, the soil was getting oversaturated, and that extra water was actually starting to harm the plants.

We’re exploring a few solutions:

• Poking holes in the soil with wooden skewers to improve airflow
• Using a fan to better ventilate the growing area
• Adding a thin layer of gravel or sand to wick away excess moisture from the surface

Regardless of which route we take, we’ll also be adjusting our watering schedule to give the plants more time to absorb water before adding more.

Now for the good news: our bacterial inoculation plants are absolutely thriving compared to the control group. They're stronger across every measurable category and just look healthier overall. We’ve inoculated all of the garden plants and will be delivering them later this week.

Looking ahead, I’m thinking this water retention issue could actually lead to a really useful summer project — especially in community gardens. If we can optimize water use, we not only prevent overwatering but also save money for the gardens that could be redirected to other needs.

Our plan is to use a tensiometer — basically, it measures how hard a plant has to work to pull water from the soil. This will help us understand soil retention levels and make targeted adjustments. I’ll share more details and updates once we finalize the process later this month.