Showing posts with label pH. Show all posts
Showing posts with label pH. Show all posts

Wednesday, February 27, 2008

Plant Food - It's Not What You Think!

At a recent Valentine's Eve Gala ballet performance, I was put in charge of the chocolate fountain. The "Powers That Be" (my eldest daughter) put me there because I am, as far as I can tell, the only human in the world that doesn't like chocolate. Now, I don't DISlike chocolate. I just didn't get that brain disease the CRAVES chocolate, so it's very easy for me "just say no." On the other hand, if they ever invented the Chicken Fried Steak Fountain, I'd be done for.

Plants have different "tastes" as well, though we would call them "nutritional needs" and I've even heard the concept described as "tolerance." It's the combination of the two things, and we don't have a single word for it in English. Some plants have very high and very specific nutritional needs, and will not tolerate a variance. Others are very laid-back and easy going, and don't require much more that sun and rain, and are even tolerant when those two conditions are not ideal. The latter is called "the ideal plant for our coastal gardens", and the former is called "orchid."

You need to know about your plants' nutritional needs and their tolerance, and then you need to know the pH of the soil you intend to grow them in. DaDUH! OK, so maybe it's not a lightbulb moment. You are saving yourself YEARS of heartbreak if you spend just a little bit of time learning about the plants you already grow, or want to grow in the future, and if you already know and understand the conditions in your yard.

So, you ask: does this mean, I can't grow azaleas in New Orleans (which boasts the most alkaline soil I've ever tested)? But I see LOTS of azaleas in New Orleans! Truth be told, you can grow ANYTHING - ANYWHERE as long as you are willing to put in the time and effort that it will take to make that plant happy in that place. Personally, I have too much to do to be outside swaddling the palms on freezing nights, or misting the impatiens during the hot days of summer. I want plants for my garden that are tough and dependable. Every now and then, I fall prey to some horticultural prima dona from Lowes' or Home Depot, and then I have to face the reality of the potting and pampering that it's going to demand of me.

Other factors in your garden that will have a bearing on your success with any particular plant are 1) the amount of sunlight that your garden receives, 2) the amount of water that is available, and 3) how willing you are to pamper your plants with proper pruning, mulching, and fertilizing. Once you have established these criteria, it's time to decide where and how to build that new bed you've been wanting.

If you want roses, and nothing but roses will do, then here's what you need:

A place in full sun—where the plants will be in full, bright sunlight for a minimum of eight hours a day. Ten's better.

Access to nearby water, so that watering daily when the temperature is over 85 degrees is not a hassle. Under sprinklers is better.

Financial resources to be spraying those roses with something every week. It will be either dormant oil spray, fungicide, liquid rose food, fungicide, systemic insecticide, or fungicide. EVERY WEEK. No vacations.

Roses are happy in a neutral soil, and won't tolerated strongly alkaline or strongly acid conditions. They like compost fertilizers.

The proper amount of sunlight is the single most important criteria. If your plant is not getting enough sunlight, it won't matter how much fertilizer you give it. Fertilizer is not plant food, no matter what the marketing people for Scott's call it. Sunlight, and sunlight alone is what your plants use to produce the sugars that allow them to grow and reproduce (flower). Amendments such as fertilizers provide nutrients that they need to be be efficient at this, but they can live without fertilizer. They can't live without light.

So now you know why antique roses are making a comeback. Modern hybrids (Tea's, for example) are finicky and prone to....fungus. There are two roses I recommend for any garden - and I have grown them both for about five years - Knockout Roses and Flower Carpet Roses. I have grown the Knockout in the bright, hot pink, the first of the introductions, and I fell in love with everything about it except the color. I have also grown the light pink "apple blossom" variety, and it has most of the charm and charisma of it's parent. It is just a "little less" across the board in my Louisiana garden (less mildew-resistant, less hardy, less tolerant of drought, etc.) The bright pink Knockout is appearing in commercial landscapes wherever I look, and for good reason. The Flower Carpets I have grown include the white and the apple blossom. Both were outstanding, low-growing plants for the front of bed. I don't remember ever spraying for black spot on any of them, and they were very dependable, blooming late into the fall, and starting up in early spring. Both have the usual rose requirements of LOTS of water (more than the novice gardener can imagine) and LOTS of fertilizer. Cut them back on the 15th of April in northern areas of coastal states (equivalent of Montgomery, AL and north) for them to come into full bloom by Mother's Day. On the Gulf Coast, I have to actually strip the plants during the first week of February and cut them back. This "forced dormancy" allows me to pick up all the leaves and branches and dispose of them (NOT in the compost pile) to prevent carry over of fungal diseases. They have resprouted and have new bloom on them within a month, depending on the temperature.

If you want to grow hydrangeas, the scenario is similar. You must know the conditions the plants like (neutral soil, LOTS of water, afternoon shade) and then you need to determine if the conditions in your yard are the right ones. If not, is it an easy fix—something that you are willing to do, or is it something that's arduous? Gardening, like everything else, is a trade-off. Pick your passion, and you will love every minute of it. Choose unwisely, and it will be a daunting task.

Next time - How to build a garden bed in the coastal south.

Thursday, February 21, 2008

pH- Part 2

This is the part where most people decide they really don't want to be Master Gardeners after all. What's all this stuff about particulates in soil and electric charges? "Nobody really needs to know this stuff," you say, "and it's boring."

Well, yes - YOU do, and no, it's not. One more short set about positive and negative charges in soil, and the pH.

The pH is a measurement of soil's acidity or alkalinity, and this one state will have the biggest impact on the plant's ability to take up nutrients from the soil - (quick review: nutrients are elemental minerals and compounds that help plants turn SUNLIGHT into sugars, which they use for growth and reproduction). On a scale of 1-10, acid is a 1, and alkaline is a 10. In reality, I've never seen a soil test register lower than a 4 - and that was in one spot in a yard in Alabama that WOULD NOT GROW ANYTHING - especially grass. Normal pH is about 7 - and if you don't know a particular plant's requirements, 7 is always a good guess.

In truth, there are plants that thrive in acidic soil (I'm talking about 6, here, not 2 or 3) and plants that won't tolerate it at all. Well known acid-lovers are camellias and azaleas, and pine trees, of course, which help maintain the acidity of the soil they grow in. This is why the clay-rich soils north of the coastal zones are prime real estate for these plants. Most vegetables do well at 7 to 7.5, and if you are growing tomatoes in acid soil, you are letting yourself in for the heart break of blossom end rot - a condition caused by the plant's inability to uptake calcium (and manage magnesium, contrarily) due to the fact that the soil is so acid. (Amend your soil with calcium and gypsum - about three years ago.) More about that later.....

WHEN you send in your soil test (please note that I didn't say "if"...) you will be asked to list the "crop to be grown." This lends itself to many interpretations, especially for the home gardener. In the front yard, you grow grass, in the back yard, you grow roses...what do you put on the form? If you are a specialty gardener, and you grow something with very specific requirements, then you need to take separate soil samples, and submit them independently. You will mark them "Front Lawn" or "Backyard Rose Garden" and you will pay for each one to be tested.

When the test comes back, they will give you the same categories of information, but in the "comments" section, the Ag Agent will tell you how you need to amend your soil - specifically for the horticultural requirements of your "crop." The recommendations for your lawn will be quite different than those for your rose garden, even if the soil samples test out to be identical (which they won't- even if your yard is very small). The test will tell you specifics about your soil: they will type your soil (i.e., sandy loam), tell you the pH and rate the amount of essential nutrients phosphorus, potassium, magnesium, and calcium, make recommendations for amendments, and give you specific comments about the fertilizer needs. Unfortunately, all of this will be unintelligible to the average human being. Don't be shy! Pick up the phone all call your county (parish) Ag Agent and ask for clarification. All this is for naught, if you can't understand the results.

This seems like SO MUCH WORK....OK - go back to the beginning of the last blog. Read again the part about "If you are serious about gardening, then you need to get serious about soil." The soil test is the most important thing you will do as a gardener. Without this knowledge, you're just tossing the seeds out there and hoping for the best. At least, when you know the condition of your soil, you can take steps to insure that the things you want to grow will thrive in your coastal garden. But in the meantime, while you are waiting for your test results to come back from the AgCenter, there are some steps to take.

Compost (isn't God cleaver?) just happens to be about a 7 on the pH scale. You can alter this by adding lime - or maybe lemon peels, I guess. But on average, composted anything seems to wind up at about 7 on the acidity scale. This makes it the perfect amendment for both acid and alkaline soils. Gee, isn't life good? Where else can you encounter the "perfect" anything?

I will get into starting a compost pile soon, but in the mean time, you can buy composted cow manure (green grass run through the insides of a cow - YUM) and you can begin adding organics to your soil right away! "Soil Conditioner" is ground pine bark, and tends to be acidic, so hold off on that until you know the pH of your soil. If you have an alkaline soil that you want to neutralize, soil conditioner is a grand thing to add. If you tend toward the acidic, but want to grow camellias and azaleas, then it's grand for your garden, too.

Next time, we'll talk about fertilizers, and understanding application rates. Now, wasn't that FUN? What are you doing inside - get out there, and get dirty!