Watering isn't a set-it-once job. As the season goes on and temperatures rise, evaporation climbs and your plants demand more water right along with it. That's the whole reason the Thirsty Earth Automatic Olla Watering System lets you raise or lower the reservoir height: you dial the water output up in the heat of summer and back down when things cool off.

The trick is knowing when to adjust. Here's exactly how we do it in our own Thirsty Earth garden.

Check it out:

1. Walk your garden and look for signs of underwatering

The simplest method costs nothing. Walk through your beds regularly and watch for stress — wilting leaves are the classic tell that your plants are thirsty.

The catch: under-watered and over-watered plants can look nearly identical. When we're not sure which way a plant is leaning, we run it through a plant-ID app like Picture This to confirm before we change anything.

2. Use a moisture meter for a second data point

Visual checks are a great start, but we've grown to love using a moisture meter to verify what our eyes are telling us. Push it into the soil and you get a real reading — another data point for diagnosing stress instead of guessing.

Here's our rule of thumb: measure about one inch away from a CottaCup. When the meter reads on the low side of "moist," it's time to raise the reservoir. That's the signal that your olla is emptying faster than the soil can hold, which happens naturally as the weather heats up.

3. Raise the reservoir when the readings drop

When it's time to increase water output, raising the reservoir height increases the pressure feeding your ollas. In our stock tank garden beds, we bumped ours from 1¼ to 1½ PSI after we stopped getting water out of the false bottom and the soil started reading on the low side of moist.

How much should you raise it? Depending on your setup, raising the reservoir six to twelve inches at a time is a reasonable jump. We use cinder blocks to prop ours up and simply add a layer to lift it, which increases the water delivered to that part of the garden.

There are seemingly infinite ways to set up a Thirsty Earth olla reservoir — our customers get creative, and almost any stable, elevated support works.

Prefer to set it and forget it?

You don't have to fuss with height all season if you'd rather not. It's perfectly fine to set your garden next year at the max height that worked this year and leave it.

Just know the trade-off: a fixed max height wastes a little water in spring, when temperatures are low and your plants are still small. Even then, it's barely a concern. The Thirsty Earth system uses such a small amount of water compared to traditional irrigation that even at your peak-summer reservoir height, you'll still be using a fraction of the water conventional methods burn through.

With current CottaCup variability, Thirsty Earth recommends a reservoir water level of up to 56 inches above your soil level — the cups can handle around 70 inches before they risk leaking, so that gives you a safe ceiling. And if you run a little high, it won't hurt anything: extra water simply drains into the water table.

The bottom line

However you choose to measure moisture — a daily walk-through, a plant-ID app, a moisture meter, or all three — the key is checking regularly and adjusting your reservoir height to match. Watch for underwatering, verify with a meter about an inch from a CottaCup, and raise the reservoir six to twelve inches whenever the soil trends dry.

Do that, and your garden gets exactly what it needs at every stage of the season. Happy gardening!

Ready to water smarter, not harder? Shop the Thirsty Earth Automatic Olla Watering System →

Frequently Asked Questions

How do I know when to raise my olla reservoir?

Check the soil about one inch from a CottaCup with a moisture meter. When it reads on the low side of moist — or when you spot wilting and confirm underwatering — it's time to raise the reservoir.

How much should I raise the reservoir at a time?

Six to twelve inches is a reasonable adjustment for most setups. Use cinder blocks or any stable support and add a layer to lift it.

Does a higher reservoir waste water?

Only slightly, and only early in the season when it's cool and plants are small. Even at max height, a Thirsty Earth system uses far less water than traditional irrigation.

What's the easiest way to check soil moisture?

Walk your garden and look for wilting leaves, then verify with a moisture meter or a plant-ID app like Picture This to rule out overwatering.

What is the max height to set my reservoir?

Thirsty Earth now recommends a reservoir water level of up to 56 inches above your soil level. The CottaCups can handle up to around 70 inches before they risk leaking, so 56 inches gives you a safe, effective ceiling. 

Even at that recommended max, the system still uses only a small fraction of the water any other method — including drip emitters — would use. And any extra water won't hurt your plants; it simply drains down into the water table.