People have been asking me this week “is the rain right now good for the farm or bad?”

Imagine that we have a meter that goes from “All good” to “all bad”.  Then insert the meter into each month of a calendar.  In December and January, rain makes the meter click all the way to the “good” side. Short of devastating floods, we are happy to get lots of rain during that time.  In June, July, and August, rain makes the meter click the other way, to “all bad”.  During the summer, rain falling from the sky has no benefit to the farm.

The rest of the months the needle on the meter moves back and forth somewhere in the middle depending on the week, the day and even the time of day the rain falls.  During these months, anything more than a quarter inch of rain means we can stop irrigating for a few days.  In general plants like rainwater better than irrigation water, and it also saves money.

We can also get into a nice pattern of alternating wet and dry weeks, allowing us time to get crops planted and then let Mother Nature water them.  That is more or less the pattern we are in right now.

Back to back weeks of rain during the fall or spring, however, start to cause problems.  We plant most crops every two weeks during these seasons.  If we can’t do so, it causes gaps in our harvest season 3-4 months later.  It also backs up the starts in our nursery that are waiting to be planted out.  Below are the summer squash plants in the greenhouse right now that we should be planting today.  By the time it dries out next week they may be too big.

Spring is also bloom time for most of our fruit and nut crops, and flowers don’t like rain much.  It keeps bees from flying and pollinating the crops.  And it brings in fungal diseases that quickly infect and kill or damage the flowers.  A day or two of rain followed by warm dry weather is not a problem.  But if the wet weather sticks around for long, some amount of crop loss is almost guaranteed.  Any time spring rain is in the forecast, we and other farmers are out spraying blooming fruit trees with preventative fungicides, but heavy rains quickly wash them off the flowers.

The closer it gets to summer, the closer the needle gets to “all bad”.  Starting with strawberry and cherry season in May, anything more than a light rain damages ripe fruit.  The same is true with tomatoes.  And harvesting crops like watermelons or green beans from muddy fields is extremely problematic.  A heavy downpour during August, for example, would destroy many thousands of dollars worth of produce on our farm.  Luckily, as we all know, it doesn’t rain very often in the summer.

Sometimes it’s the little things.  The boxes we use to harvest most of our summer crops are not waterproof, because the crops are rarely wet and we don’t wash them.  During the summer, we store the boxes around the edges of the fields where we are using them — thousands of them.  An unexpected and sudden thunderstorm in July can instantly ruin all of those boxes.

As far as this week’s rain is concerned, the meter is somewhere to the left of center, say 60 percent good. None of the crops we’re harvesting now are hurt by rain.  Since we’re still in a drought, we need all the water we can get to fill reservoirs and the soil profile.  This particular storm was a good one for that.  And last week was dry enough to get some planting done, and next week looks dry as well.  So we won’t get too far behind in our work.

Unfortunately, our trees and vines are ahead of schedule in their blooms.  Wherever you look now — apricots, grapes, peaches, pears and pistachios — you can find the signs of fungal infection.  We will be struggling with those diseases in the coming weeks and months and they will affect the harvest.

There is no way that California can catch up on rainfall for the season at this point, even if we end up having the wettest April in recorded history.  Average rainfall in April is just a fraction of what we get in a normal December or January, and this year we got close to nothing in those months.  200% of average would still be just a fraction of what we need.  But it would cause a lot of problems, on our farm at least.

With a powerful El Nino brewing out in the Pacific, chances look pretty good that storms next winter will end the drought of 2013/2014.  So as far as we’re concerned here at Terra Firma, we hope yesterday’s storm will be the last big one until then.