Dirt, pH and the Big Three
Updated: Oct 17, 2018
The weather is still unpredictable as of this writing. Mid-fifties one day, below zero the next. It’s still too early to start inside seedlings and, of course, early crop radishes and lettuce are at least six weeks away. One good thing about this fluctuation of temperature is that it confuses the bugs. It is a cycle that can do more damage to their world domination than any other. Let us keep our fingers crossed. But, beyond enacting a voodoo spell on your back yard insect community, what else can be done right now to prepare for this season’s new garden?
I think this might be the perfect time to start your soil testing for the new year. If you can get a spade into your ground and extract a reasonable sample, you can get that ball rolling. A sample roughly six to twelve inches in depth, about an inch thick is all you need. Bring it into the house, let it dry out, sift out major stones (or in the Urban Farmer’s case, glass, marbles, etc...) and decide how you want to proceed. There are home soil testing kits available, little battery-operated gadgets that test pH and nutrient levels, and my favorite, the Kenton County Cooperative Extension Service.
The Kenton County Cooperative Extension Service will provide one free soil test sample to every Kenton County resident. What’s not to like?! They will provide you with a detailed analysis of your garden’s nutrient levels, pH, and soil organic matter. Also, they analyze the results, according to your particular needs, and make recommendations on what you can do to improve the condition of your soil.
Usually, the soil sample that is recommended is a composite from different areas of your garden blended together. Being from a long-established agrarian background, I had a greater curiosity to know EXACTLY what each little area of my garden was about nutrient-wise. Honestly, I submitted five samples from a six hundred square foot garden, and they indulged me! I offered to pay extra, but nothing came of that. What a nice group of people! Actually, I think that this service might be a little under-utilized and that’s why they let it slide. So, in promoting this service to all of you, I may have just shot myself in the foot. Anything to further the cause of urban farming.
I prefer the Cooperative Extension Service report because it is so detailed and so full of information that it really is a valuable learning tool. And because the results are from YOUR garden, it really sticks with you. You can see the results yearly of what you did to amend your soil and how it played out, for better or for worse. Couple this report with a few good, preferred gardening books and a whole world of clarity in gardening is yours!
The four most important items in any soil report are firstly pH, and then what I like to refer to as THE BIG THREE: Nitrogen, Phosphorous and Potassium. There are other lesser nutrients, equally important, of course, but pH and the big three are the most valuable to get a handle on.
The measure of acidity or alkalinity of your soil is the pH level, calibrated by a numeric system of one through fourteen. “One” being highly acidic and “fourteen” highly alkaline. A nice balance is the key here. Six to Seven roughly (seven being neutral), is the range agreeable to most vegetable plants. This is the level you want to shoot for. Plants prefer a good, agreeable pH level in order to utilize the nutrients they need. You can adjust this level up or down by adding appropriate amendments. To raise the acidity of your soil, adding lime will do the trick. There are several forms of lime you can utilize and a detailed evaluation of your soil test will steer you toward the right one. To lower your pH in order to make it less alkaline and more acidic, acidic organic matter (pine needles, peat moss, etc.) or sulphur will do the trick. As in all soil amendment strategies, the sooner the better. You want as much time as possible for the changes to settle in and blend with your soil.
Nitrogen is where green comes from. It plays a fundamental part in the formation of chlorophyll. It is quite ephemeral as it gets used and needs to be replaced regularly in a garden. Nitrogen is actually released into the atmosphere every time lightning strikes…a fact! But, you will always have to add nitrogen to your garden anyway. Compost is a good way, and I have had good results with organic blood meal. Leafy plants like kales, lettuces, etc…love nitrogen. Fruit-bearing plants are a little more particular about it. You have to be careful about when you apply nitrogen to your flowering plants. Excessive nitrogen causes blooms to drop, and voila! No tomatoes. Or peppers. Or eggplant. Infuriating. Once, many, many years ago I decided that I was going to have a tomato plant in a pot on my back patio. This is before I moved to Covington. I thought to myself “I am going to have the best tomato plant on earth and I’m going to feed it every day!” I did, and I did indeed have a majestic plant….without a single tomato on it! Lesson learned. Feed your tomatoes after they have set fruit. Not until. Trust me on this.
Phosphorous is important for the efficient growth and formation of flowers and fruits. If you see a purple cast to the leaves on tomatoes, that is a clear indication that you have a phosphorous deficiency. It is very common. However, if you do, be very judicious about applying phosphate to your garden. It breaks down very slowly and if you overdo it, it will take a while for it to reduce to a more beneficial level. Adding compost will “dilute” it and help break it down. So easy does it. How do I know? How else. I’ve done it myself. Gardening is a process of learning through successes and mistakes. It’s like life, but more enjoyable.
Potassium is a little harder to appreciate, only because it doesn’t show it’s qualities as obviously as Nitrogen. It works on a more covert, though very important level through photosynthesis (with nitrogen), formation of proteins (actually affecting the nutritional value of your veggies) and fostering good soil health. Greensand is the recommended solution for correcting any deficiencies. It is marine sourced and is also an excellent soil conditioner. I don’t have any personal experience with this problem……yet.
So grab your spade, find a patch of dirt you can dig in and get that sample. I think earlier is better if you are going to use the Kenton County Cooperative Extension Service. I imagine they are pretty busy in early spring. Even more now, since I’ve just bragged about their gracious generosity. It’s a great service and it’s free!
Copyright 2017 Ginger Dawson