The PH Scale

Ann-Marie Volz • March 8, 2019

PH Made Easy

Either talk about gardening or read about gardening, and inevitably, up comes the subject of soil PH, a subject many people find baffling. Here are a few simple things to make the subject a little easier to understand.

First, PH stands for "potential hydrogen", but you can ignore that if all you are doing is trying to grow a nice garden. The PH scale is a measure of the acidity or alkalinity of a solution, with numeric indicators from 0 to 14. For a gardener, knowing where your soil tests on this scale may determine what you plant, or what you may have to add to your soil to plant what you want.

The PH affects the availability of nutrients for uptake by a plant. Evergreens are generally acid loving plants. Rhododendrons, azaleas, and mountain laurels are examples. But maples and oaks also enjoy acidic soil.There are plants, however, that prefer or tolerate alkaline soil, like the ornamental grasses Pennisetum (fountain grass) and Miscanthus (maiden grass), often planted for their deer resistance. So too, the much loved garden favorites purple coneflower, bleeding hearts and creeping phlox.

Now for the scale. Seven is considered neutral. Most plants that do well in the twin tiers of NY and PA, where I am located, perform well in slightly acidic to neutral soils. Acidic soil measures one to six, above seven is considered alkaline, which is sometimes referred to as "sweet" soil. An easy way to remember this if it flip flops around in your head is to count the number of letters. Acidic has six letters, alkaline has eight. Six and below is acidic, eight and above is alkaline. isn't that easy?

When it is desirable to move your soil from highly acidic to neutral, you can apply agricultural lime, following the recommended guidelines for amount applied per square foot. To reduce PH around acid loving plants, work compost, leaf mold (more on that later), or peat into the soil before you go fertilizing with chemicals. Why? Remember that PH affects nutrient uptake - not just the big guys like nitrogen, phosphorous and potassium, but secondary nutrients like calcium, magnesium, and sulphur. Nutrients do not work in a vacuum, they work together. Your plant may have all the nutrients it needs in its' surrounding soil, but cannot take them up because the PH is off. Fertilizer will not help much if the PH isn't right.

You can test soil PH with a kit available at many stores and online, you can send your soil to a local conservation district for testing, or, for a quick indicator, you can try an old fashioned approach I learned from a gardening book some years ago. When your soil is wet (not wetted by you), take a tablespoon or so and add a pinch of baking soda. If nothing happens, your soil is likely neutral or above. If a reaction occurs, like fizzing, your soil is acidic. You can also try the opposite approach with vinegar. Using another wet soil sample, add a bit of vinegar and see if that sample reacts with a fizz. If it does, your soil is alkaline. The bigger the reaction, the more alkaline your soil is.

Information about your plant, shrub, or tree's PH requirements are sometimes on the tag, can be found online, or is likely available in a good old fashioned gardening reference book. Plants don't talk, but they do speak volumes through their appearance. If a plant does poorly, checking the PH requirements and the soil is a good way to start a dialogue, so to speak, and get your plant back on track.

Good luck. Remember, all gardeners are in a constant state of learning. Feel free to share your questions and comments, because I love to learn!

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Landscape Fabric

By Ann-Marie Volz • February 12, 2022
Landscape fabric is a real pet peeve of mine. I have ripped out so many hundreds, maybe thousands, of feet of landscape fabric in my time that I would, if I had the money, take out full page adds in every major publication to tell people to STOP using it in gardens. However, it does have its' uses, as you will see in a moment. First of all, landscape fabric is often sold as a method of weed control. So, let's discuss weeds for just a moment. Weeds that grow in your garden arrived there by one or all of the following ways. They grew from a weed seed that was blown into your garden by the wind or transported there by an animal (i.e. bird droppings) or insect. Or, they grew underground from a nearby location. Some weeds (which is any unwanted plant) can grow very long distances underground! Members of the mint family travel quite well this way. Finally, weeds also grow overground. Ground ivy, a bane to lawn lovers and gardeners alike, is this kind of traveler. Now back to fabric. Fabric will not stop any weeds from growing in your garden. As for the weed seeds, they will sprout in mulch or even stone and the fabric you've painstakingly put down may slow their progress. But most weeds have roots so fine that they can and will weave through the fabric. If you get them before, or just as that process starts, well then, you can say the fabric worked. And by get them , I mean WEED. So, now you are busy pulling weeds so that they do not root into your fabric. How is that different from weeding so that weeds do not root into your soil? I wonder! If you don't get that weed in time, then the roots will grow and when you try to pull out that weed, you will tear your fabric and, very likely, leave enough root matter behind for the weed to grow right back, and better, now that you've made a nice hole in the fabric. As for weeds that grow underground, now there is a real danger to gardens and landscapes. Why? Because those underground runners are looking for a place to surface and grow. I have lifted fabric in established gardens to find massive networks of such roots and runners. Sadly, they often surface at the crown or your plants, that is, where you have cut a hole in the fabric to plant your flower, or shrub or tree. And, chances are , you will not notice it down there until it is far too enmeshed with your prized plant to ever get it out. This is a terrible thing and I've seen it happen over and over again. Those underground roots and runners will also find a place to surface at the edge of your garden, where the fabric stops. And they will surface and grow there with reckless abandon. At that point, the unsuspecting gardener will start pulling, and discover with dismay, that everything they are pulling is attached to long roots and runners. And now, oh what a mess, the fabric is completely pulled up! Fabric may more successfully slow down the progress of weeds that spread by growing overground. And, it may be easy to pull these culprits out of the garden as they struggle to take hold through the fabric. But of course, that amounts to diligent weeding, and I'm pretty sure most people buy and use fabric because they think they will not have to weed. Still, I am a professional gardener and I do buy landscape fabric. Why? For two reason and two reason only. Number one, fabric, even if you have to use cheap fabric, should be applied under stone and gravel. Notice that I have it employed in the picture above. It provides a barrier that prevents your stone and gravel from sinking into the soil below over time. Weeds sprout in stone and gravel eventually, but can be treated with a dash of boric acid, or some other natural herbicide. After the weed dies, it can be removed without making a huge hole in the fabric. Number two, high quality, non-woven fabric can be used by itself as a pathway in vegetable gardens. It will get slippery, so care must be taken to keep it clean. Non woven fabric has the look and feel of thick felt. And it is the only fabric I will use in my two exceptions for using fabric. Here are two more reasons to avoid fabric in gardens and landscapes, which have nothing to do with weeds. Gardens are a process. The soil around your plants should be cultivated from time to time, and amended with organic matter. If you use natural mulch, it is supposed to break down and be reapplied every so often. You can't do any of that when fabric is present. And the truth is, all fabric will eventually get ripped out and thrown into a landfill, and I think it is high time we all become more conscious of how much we send to the landfill! There are those who use fabric seasonally in vegetable gardens. I used to do this myself. But I have been converted to using straw or hay or cover crops. Any or all of which look better, work better, save money, and return organic matter to the soil. So, in conclusion, if you are going to have to weed anyway, why spend your time and money on fabric? But if you are doing anything with stone or gravel, make that anything last longer and cleaner with a layer of fabric beneath. Your comments are welcome! Gardeners learn from gardeners.
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