Deep Watering is a Myth
The myth prevails to this day. We still see many gardening websites and content creators saying to water deeply and infrequently.
This is an inferior and inefficient way to use water.
For one, about 90% of all roots exist within the top 3 feet of soil. The top foot of soil has about 70% of all roots. There are so many people claiming that plants send roots deep down into the soil but this just isn’t the case. Sure, some plants can send taproots deep down into the water table, like mesquite, but the majority of their roots are in the top couple feet of soil.
Knowing this, should we let this soil dry out? Nope.
Yet deep, infrequent watering does just that. If you only water once a day for 30 minutes, especially in the summer, then your soil is going to dry out.
It’s just what happens when you’ve got plants growing and the sun shining.
Another reason that deep watering doesn’t work as well as shallow watering is because plants need consistent water as they photosynthesize.
Remember, plants don’t develop massively deep root systems. Their roots need water consistently to do basic photosynthesis. It’s better to give them water throughout the day rather than once. They get a new replenishment of their nutrients when you water frequently.
Also, with deep watering, many times you will get runoff accompanying this practice. Runoff is wasted water and a wasted resource. Runoff can either occur at the surface or deeper in the soil.
The solution to this deep watering myth is to utilize pulse watering, a highly efficient irrigation schedule.
Instead of watering once a day for 30 minutes, you would water 6 times a day for 3 minutes. It cuts the total amount of watering by over half.
This is especially effective with drip irrigation because the foliage doesn’t get wet yet the soil stays nice and moist at consistent time blocks.
It depends where you live on how much you need to water and how many times per day.
Right now, where we grow, the temperatures are regularly going over 100 degrees F. It’s extremely dry as well. We don’t get any rain from May-September.
We are still getting away with watering with this schedule:
6 times a day, 2 mins = 12 mins total per day
The growth has been fantastic.
Play around with different times and lengths to see what works for you. If we see runoff, we know we need to back off the amount of watering. If things are starting to dry out, we can increase slightly. It all depends on your climate.
One more thing to say is that watering at night does nothing for your plants. They don’t need water when they aren’t photosynthesizing. They need it during the day when the sun is out. You are replacing the water that has left via evaporation and transpiration.
Focus on giving your plants what they need when they need it and you’ll see why this is a better way to irrigate.
