Watering the Garden

I’ve been dragging hoses and hauling watering cans for the past several weeks so naturally this week’s blog is about watering. In my travels around town I’ve seen a few watering "no-no’s."

Neighbor Ed's garden--looking good

First, it takes up to two years for plant material to fully root in so if you have newly planted landscaping make sure they get 1" of water a week. A well established plant and grass can certainly handle a little drought but drought does stress the plants and make them more susceptible to disease even into the following year

Second, water in the morning so that any water that splashes on to the leaves has a chance to dry before evening. This will reduce the opportunity for disease.

Third, water the soil, not the plant. I noticed my neighbor Ed, whose garden is looking quite lush, water with a sprinkler the other evening. Watering from overhead is very inefficient because of evaporation. Water will also splash up onto lower leaves and can invite soil borne diseases such as tomato blight. Watering in the evening also can provide an opportunity for diseases, since they thrive in moist conditions.

Put the hose at the base of the plant
to ensure proper watering

When water trees and shrubs, especially newly planted ones, place the hose right up to the base of the plant and leave it on a slow trickle for awhile. This allows the water to penetrate the root ball from the center and then move out into the surrounding soil and encourages the roots to grow out in the same direction.   

And one last thing on the watering front: Lots of people, including me, garden in containers and not just flowers but vegetables as well.  I have two whisky barrels that I plant up every year with tomotoes, peppers, eggplant and some herbs every year.  If you grow tomatoes in containers it is very important that you water them consistently.   Tomatoes require calcium to prevent a problem known as blossom end rot.  There is usually enough calcium in the soil from fertilizers to provide enough calcium but if they get too much water so that the calcium is diluted or not enough water so that they cannot pull enough up through their roots you will notice a "water spot" on the blossom end of the tomato.  Eventually it turns black and starts to rot.  If you notice this happening there are foliar calcium products on the market that you can spray on the plants to prevent it but also remember to water regularly.

To Water or Not to Water

You know, it seems like it’s either feast or famine. This spring was one of the wettest, especially in Iowa with all the flooding that occurred there, and now hurricane season is hitting Florida and Texas. And we haven’t had rain in weeks! Not that I am complaining but if your lawn is like mine it looks like shredded wheat. So, what to do? Unless we have an extended drought your lawn will do just fine. It is now going dormant, but it is not dead. You can water but you must water on a consistent basis and follow whatever water restrictions your municipality has implemented. If you do feel the need to water, follow these guidelines: The lawn will need 1" of water per week, water deeply and infrequently rather than a little bit every day and finally, water in the morning rather than in the evening to prevent disease. Water is a scarce commodity and it does seem silly to use it on the lawn, when as soon as the rains return, it will green up again. I say enjoy the break from mowing.

Your trees, shrubs and perennials are a different matter, especially since these represent a large investment. I found these watering recommendations on the Tree Gator web site:

1. Water slowly and deeply. Tree roots are in the top 2-4' of the soil.
2. Apply water directly over the root ball.
3. Newly planted trees need approximately 10 gallons of water per week per 1" of tree caliper. A 2" caliper tree would need 20 gallons of water per week.
4. It takes a tree about one year per caliper inch to become established. So, our 2" tree will take two years to become properly established.
Tree Gators are bags that fit around the trunk of the tree and are filled with up to 20 gallons of water. The water is released slowly through the root ball and out to the surrounding soil. This encourages the roots to grow out of the planting hole and results in a better established tree.
Soaker hoses are another option if you have a larger area that needs to be watered, such as a perennial bed. They can be snaked around the plants and can even be buried underground to more effectively deliver water closer to the plants’ roots. Using soaker or weeper hoses keeps the water in the soil and not on the foliage.

Sprinklers are definitely not the way to water. A lot of the water evaporates before it hits the ground and water on foliage promotes disease. If you only have one tree or a small area, just lay a hose on the ground next to the tree trunk or plant stem and leave it on a slow trickle until the ground is saturated.

You may have noticed your older, more established trees starting to turn color a little early. This is a stress response due to the drought, similar to the lawn looking like toast. Even if the tree is in a lawn that is being watered, the tree is still not getting enough water deep enough. It, too, will benefit from a good, deep soaking from the hose. Believe it or not, but a lot of these trees probably have not fully recovered from the drought of 2005.

Well, I've just noticed I've got a little hose draggin' to do myself!