It rained Tuesday night. Now what?

Every app can show you a calendar. None of them can tell you which of Wednesday's lawns actually grew. We measure the rain that fell on each yard since the last time you cut it, which is a different question and the one that decides the day.

One lawn, two readings. The grass grew normally and the ground is still too wet, which is why these are separate questions.

Since the last cut, not the forecast

A forecast tells you whether to send the truck tomorrow. It says nothing about whether there is anything to cut when it gets there. Ten days in a cool wet May and ten days in a dry August are not the same lawn, and days since the last visit cannot tell them apart. Rain is what actually grew it, so rain is what we count.

The four things it will tell you

And it says nothing at all unless it is one of them, because a note on every job every week is a note you learn to scroll past.

It probably has not grown

Under 0.25in of rain a week since the cut. Worth asking whether this one is worth the trip.

An ordinary week

Between the two. We say nothing at all, which is most weeks.

It grew fast

Over 1.75in a week. The kind of week where going a day early is easier than the double cut later.

Too soft to put a mower on

1in or more in the last 3 days. This one outranks the rest: it does not matter how ready the grass is if you are going to rut the lawn.

It never moves anything on its own

You get an observation and a button. When a day is a write-off you tap once, and we move what can move, skip what is on a longer cycle, leave anything on a fixed day where it is, and email everybody affected. What we will not do is reshuffle your week overnight and let you find out from a customer.

Two yards are always going to be different

Mark a yard as irrigated and we stop suggesting you skip it in a dry spell, because sprinklers keep it growing when the rain does not. That is the only thing irrigation changes: a watered lawn gets every bit as muddy as any other after an inch of rain.

Or turn the weather off for a yard entirely and we will leave it alone. A contracted visit count, a customer who complained about a skip, a lawn you just know is odd. The model cannot know those and should not argue with you about them.

What it cannot do yet

The thresholds above are a starting point, not turf science. They are shaped by a normal week in central Illinois, and they are adjustable per account precisely because that is the wrong shape for Phoenix or the Gulf coast. We would rather say that than pretend a number is calibrated when it is not.

Rain is also measured on a grid about seven miles across, so two customers on opposite sides of a line get theirs measured from slightly different places. At the scale a thunderstorm varies on that is fine. It is not the same as a gauge in the yard, and we are not going to tell you it is.

Questions about rain and mowing

How long after rain should you wait to mow?

Hours is the wrong unit. What matters is whether the ground still holds a footprint and whether the grass is standing up - an inch on hard-baked August ground drains by lunchtime, and the same inch on clay in April does not. We flag a yard when about an inch has fallen in the last three days, which is roughly where a mower starts leaving ruts instead of stripes.

How much rain is too much rain to mow?

Our starting point is an inch in three days for ground that is too soft, and under a quarter inch a week for grass that probably has not grown enough to be worth the trip. Those are a starting point rather than turf science, they are shaped by a normal week in central Illinois, and they can be moved per account for a reason.

Does it reschedule my route automatically when it rains?

No, and that is deliberate. You get an observation and a button. Tap it and we move what can move, skip what is on a longer cycle, leave anything on a fixed day alone, and email everybody affected. What we will not do is reshuffle your week overnight and let a customer be the one who tells you.

What about lawns with sprinklers?

Mark the yard as irrigated and we stop suggesting you skip it in a dry spell, because sprinklers keep it growing when the rain does not. That is the only thing it changes - a watered lawn gets every bit as muddy as any other after an inch of rain.

Put your own yards in and watch it for a week

Free for 10 yards, no card, and the rain signal is on all of them.