Watering in the Summer
I’m sure that some of you have noticed some of your plants looking a little bit stressed with the onset of hot weather and suddenly no rain. Even when you water, things still look a little bit droopy. The main reason for this is that our plants have gotten used to having plenty of rain – in fact, TONS of rain. They haven’t developed deep root systems because of the rain AND/OR they have had their root systems damaged because of all the rain. I watered this morning, and I’m still noticing plants wilting in the heat of the mid-afternoon sun. These plants just aren’t able to pull up enough water to make up for what they’re losing.
It can be really tempting in this situation to just keep pouring on the water, but that isn’t the best thing to do. You want to water regularly, but try to gradually wean your garden off of inches and inches of water each week. One thing that will help you do that is to have an idea how much water you are actually giving your garden. Since we have a drip system, here’s what I did:
I buried a plastic lid (about 1.5″ deep) under one of the emitters, and then turned the system on for 1 hour. After 1 hour, my catch cup was just starting to overflow a little bit. When I saw that, I thought to myself, “I can’t believe that I’m putting a whole 1.5″ of water on in only 1 hour, but…I guess I’ll turn it off.”
Silly me. As I’m sitting here thinking about it, I realized that technically, yes, that one spot had gotten 1.5″ of water, but our drip system has emitters only every 12″. Water tends to soak into the soil in a rather triangular pattern. Let’s see if I can explain this clearly. (Probably not, but here goes nothing.) From one drip, the water soaks into the soil, but instead of soaking straight down, it spreads out as it soaks in. (Okay, it just took me 10 minutes to find a reference for that! Here’s a link to a rather poor drawing.) In clay soils, the water spreads out more, and in sandy soils the water soaks in straight down more. Our soil is really rather sandy with high organic matter and not as much clay as you might think. It’s a blessing most of the time, truly! However, that fact means that with emitters 12″ apart and 2 drip lines running down a 4′ wide bed, it is actually pretty hard for these beds to get a good, uniform, thorough drink of water. I should have let the drip system run another hour before turning it off, and even then I should probably plan to hand water any young seedlings that are growing in between the drip lines. (Poor summer lettuces!)