Watering tips and other helpful hints. No one can give you everything you need to know about watering but we hope this helps.
Water Water, How much water? Too much, too little? Too soon or too late.
How much to water, when to water is always a challenge. We hope the information below will be helpful. Credit for much of the content goes to a wonderful nursery, Wegmans Gardens a Redwood City, CaliforniaEvelyn has taken much of Wegmans information and adapted it to or San Diego climate. Always double check anything you read to make sure it applies to your situation. . It is smart to first look at where it is from. Advice from the United Kingdom is not going to work in San Diego. University sites are often your best source of really good information.
A very good source for more help is your local Master Gardener assoc. Go to San Diego Master Gardeners www/.mastergardenerssandiego.org/.San Diego Master Gardeners are volunteers trained and supervised by the University of California Cooperative Extension (UCCE) to provide research based answers to your gardening questions
To gauge whether your plants are getting adequate water, check the depth of moisture in the soil the day following watering. Soil around trees and shrubs should show moisture to 12 inches down and do not need water again until the top 3 to 4 inches of soil is dry. Where one emitter was sufficient when a one-gallon tree or shrub was planted, now, two or three years later, two to four emitters spaced 12 to 19 inches from the trunk at the drip line may be necessary. If you are not sure about moisture depth, we recommend that you get and use a Moisture Meter. When you use your moisture meter, be sure to keep the tip of the probe clean and push it into the center of the root ball as well as into the area between the trunk and drip line. You can also check outside the drip line just for your own information. What is the Drip Line? That is not a stupid question. That is the circle around the tree under the outermost area of leaves where water would drip down onto the ground.
Check your irrigation systems for leaks and broken or malfunctioning parts. It is easy for those little emitters to get plugged with a bit dirt or algae. If they are, clean and rinse in a 10% bleach solution. Check also for adequate coverage. You may need to add emitters on drip systems for maturing trees or shrubs as they increase in size or you may need to adjust the length of time the system runs. If you are using sprinklers with a spray put out a half a dozen or more pie tins in different areas to see how much water is actually going where it can do the most good. ulching to save water;
Always mulch to save Water. Mulching consists of covering the soil with a 2 to 4 inch layer of organic matter (Fir bark, Fir compost, Redwood compost, Pine needles, Oak leaves, straw, rice hulls, etc.). You can mulch with 1 to 2 inches of gravel or even 4 to 6 layers of newspaper, but the layers of organic matter are best. There is a shredded Redwood bark, sometimes referred to as “gorilla hair”. Ok for paths, but not for mulching. Its main drawback is that it packs down, and is almost impervious to water. Rain water or sprinkler water does not go through it into the soil thus defeating one of the main purposes of mulch. Do not mulch within 4 to 6 inches of a tree’s trunk.
For your Roses and other shrubs. For most drip or spray systems, one time a week for one to one and a half hours should be adequate and should provide five to ten gallons per bush. It’s best to water your Roses foliage in the morning in order to decrease the incidence of rust and mildew.
Planting and watering hints. New plantings of 4 Inch bedding plants and other shrubs or trees. This is a really important part that sometimes gets missed and then your new plants die.
Evelyn’s hints. Always dig your hole much bigger/ wider than you think you will need. Take the soil out and amend it with some good soil amendments if needed. Not too much because you don’t want your plant to get so comfortable with all that good soil so the roots don’t want to move out into the real soil.
Water your plants really well before you plant. Water the hole that you dug and the extra soil too. If the roots are all going around in circles tease them apart of make some cuts so they have to go out into the new soil. If you add any fertilizer at that time be careful, sprinkle it into the bottom of the hole and cover with some soil before you plant. Plant your plant and tamp the soil down around it to be sure that all the roots have soil next to them. Water again. Then remember that until those roots do move out into your soil you need to water more often. This can take several weeks or more. Watch your plants to see when they begin to wilt as one sign that they need water. Watering for Trees Water established trees once a month June through September for a few hours with bubblers at the drip line to ensure a deep soaking. You can also build a berm just beyond the drip line at least 4 to 6 inches high and flood monthly. Newly planted trees (one year or less) should be watered in a basin for about one-half hour, once a week. A good test for watering newly planted trees and shrubs is to water the newly planted and amended hole until the water pools and stops bubbling.
A bit about Citrus.
Citrus trees are often full of almost all of the sucking insects. Just printed help for now. Images come along later. There are lots of good images on line and a simple google search will bring them up for you to see.
Summertime is a good time to prune Citrus if needed. Prune out dead wood. Thin the branches that need it. Check for snail damage. Snails love to stay on citrus trunks and branches and wait for some moisture to do their damage. You may have to knock them off with a stiff brush to get them down where the snail bait is.
Citrus trees often have lots of different insects and pests. Scale, Mealybugs, Aphids, Leaf Miners, Thrips you name it and your citrus probably has it.
Black sooty mold. Ugly black sooty mold covers the leaves. That is a sign that your plant has one or more of the pests listed above. The mold grows on the sweet honeydew that these insects secrete. It is unsightly but unless you have a huge amount not too damaging. Scales are really common on Citrus. There are two main kinds of scale. One looks like little brown shells and the other is really flat. Google in types of Scales to see some images and help you learn.
Scale is a sucking insect that usually clusters along fruit stems, new growth and the undersides of leaves. If scale is found, UC recommends that you spray three times at two week intervals with a mixture of Malathion and Horticultural Oil. Don’t use horticultural oil more than 4 times during the growing season. Don’t spray with Horticultural oil if your citrus is blooming. Wait at least 2 weeks between applications and don’t spray if temperatures will exceed 85 degrees (F). Citrus leaf miner usually attacks young citrus trees. As they get old the leaves are too tough. You can see the little wavy pathway inside the leaf. Any of the Spinosad sprays will work but you only want to spray when you see active mines.
Mealy bugs look like a white cotton sticky mas. Almost always in that crotch that is where leaves or stems join the larger branch. Very difficult to get rid of them entirely. Sometimes it is cheaper and easier to destroy the plant and the soil instead of trying to eliminate it.
There is such a variety of insects, diseases and virus’s that no one can know them all.
Bring in your samples in good tight plastic bag. Be sure they are big enough to really see what is going on. When we can’t tell you what the problem is you have a wonderful resource available. It’s free, our taxes pay for it and it is worth every penny. Every County in America has a County Home Ag Department. They are under the University of California Cooperative extension office. They have teams of volunteer Master Gardeners that are ready to help you by phone, email or in person. You can bring in samples or email photos
Go to San Diego Master Gardeners www.mastergardenerssandiego.org/
San Diego Master Gardeners are volunteers trained and supervised by the University of California Cooperative Extension (UCCE) to provide research based answers to your gardening questions