I try not to water most of the landscape plants unless they really really are in need. In other words, in my perennial garden and with the trees and shrubs, I will generally water in late August if we have had a dry spell.
In the early part of the season if I just planted new perennials I water on a regular basis if it’s dry. Same thing with newly established trees and shrubs, for at least the first five years.
However, my watering approach in the vegetable garden is different due to the fact that the crops being produced have a very high water content and therefore, need adequate moisture.
For example, here are a few vegetables and their percent water content: Red tomatoes (94); peppers (92); broccoli (91); cucumber (96) and zucchini (95).
Therefore, if you are not providing water to the vegetable garden to keep the soil evenly moist, your produce won’t develop as they should.
A few seasons ago, we had a July and August with regular rains at my house. The peppers were the best they have ever been. The walls of the peppers were thick and the taste was outstanding.
On the other hand, in years that I don’t keep them watered, the peppers have thin walls and a bland flavor.
Another issue we see in the vegetable garden when the rain isn’t consistent is blossom end rot of tomatoes and squash. This problem occurs when soils are either really wet or really dry, in other words during extremes in soil moisture.
Blossom end rot occurs when soils are either really wet or really dry for an extended period of time. It is due to the fact that the plants can’t take up the calcium in the soil. Applying calcium or sprays won’t help.
We can’t control blossom end rot when soils are wet and we have continual rain such as we did last year. We can, however, control the extreme dry by providing the inch of water a week.