Lemmy’s allowlist feature is generally recommended against. It limits federation to only that list, which makes discoverability harder than it already is.
For a self-serving instance, it’s more tenable to use a blocklist and federate normally.
I use the Ecowitt moisture sensors for potted plants. Given their size, I wouldn’t recommend using them for your lawn because you have to be sure to not hit them when mowing.
Automated irrigation systems are reasonably consistent. I moved from my lawnless apartment to a house with a backyard of grass. I left out a few empty containers across the lawn, waited for the first watering cycle, and adjusted the timings based on the distribution.
Every day, that list of people grows: https://xkcd.com/1053
US states. If I have more than 50 different host names to manage, I should re-evaluate my hobbies. And then lazily move on to US state capitals.