Tag Archives: soil acidity

Understanding Soil Tests

If you’ve never had your soil tested you may want to consider it. While soil tests may seem like something more suited to commercial growers than backyard gardeners they’re actually quite simple and affordable. In fact some local extension agencies and/or state colleges offer this service for free. While you can purchase at home soil tests generally having it professionally done is a good place to start. 

Here’s what you can expect from a soil a test and what it will mean for your garden. 

Macronutrients

Primary Nutrients

The following three nutrients are considered the primary nutrients and the probably the most discussed by gardeners.

  • Nitrogen 
  • Phosphorus 
  • Potassium 

Nitrogen is important for plant’s vegetative growth. Phosphorus helps in root and flower development. Potassium promotes vigor. These are found in a variety of commercial fertilizers and homemade garden amendments.

Secondary Nutrients

  • Sulfur 
  • Magnesium
  • Calcium

Calcium helps plants build strong cell walls, magnesium is an important part of chlorophyll, and sulfur is important for the growth of roots and seeds. Just like primary nutrients these secondary nutrients can be purchased in commercial amendments or you can make homemade ones.

Micronutrients/Trace Minerals

Some soil tests will give you the option of testing for micronutrients or trace minerals. These are minerals that plants need in very small amounts. 

  • Boron 
  • Chlorine
  • Copper
  • Iron
  • Manganese
  • Molybdenum
  • Zinc

Unless you suspect a problem testing for these is probably unnecessary. Most soils have enough to keep plants healthy and deficiencies in these minerals aren’t caused by their lack of presence in the soil rather an inability for plants to take up the nutrient because of other problems such as drought stress or incorrect pH. 

These minerals are also typically present in large enough quantities for gardens in any organic fertilizer or other amendments even simple, good quality compost. 

Soil pH Level

Another important part of your soil test is your soil’s pH. pH is the measure of how acidic or alkaline your soil is. It’s an important feature on your soil test as it affects soil nutrient availability and microbe activity. This means that even if a nutrient is in your soil it may still be unavailable to plants do to your soil’s pH.

It’s also worth noting that some crops like blueberries and potatoes prefer more acidic soil than others. 

Amending Your Soil

Once you get your results you can amend your soil as needed. There are a variety of products available commercially or you can use homemade garden amendments like compost and compost tea, manure, coffee grounds, egg shells, pine needles and more. 

You may be able to get personalized recommendations from your local extension agency or soil testing service.

When adding any garden amendment it’s important to thoroughly research its effects on your garden. Certain amendments like oyster shells for calcium can affect your soil’s pH and may affect the availability of other important nutrients. You also want to avoid adding too much of anything to your garden as this can be just as bad as too little. Excess nutrients can also run off into streams and other water bodies causing toxic algae blooms.

11 Free Organic Methods to Add Nutrients to Your Garden

Seedlings

If you start your own transplants at home don’t forget about the nutrients they need. Buying or mixing a good quality potting mix is important to their success. One of my favorite ways to give seedlings a quick boost is to add a bit of compost tea or liquid kelp to their water. I typically use about 5 TBS per gallon of water. 

Pin it for later.

Mulch Ado…

Not all mulch is created equal.  Types of mulch range from great to not-something-you’d-want-in your-garden.

The Compost Solution

If you’re looking for a rich, black mulch containing ample nutrients for your plants, the answer is simple—use garden or kitchen compost!

Hay and compost used for mulch

If you’re going to compost organic materials yourself, make sure to have just the right balance of brown (carbon-rich) and green (nitrogen-rich) materials, so that your compost will break down efficiently. If you don’t have a lot of material to work with and if quick-and-easy composting is of the utmost importance to you, you might want to invest in a compost tumbler. But here at Southern Exposure, we do it the old-fashioned way! If you, too, have an open-style bin, make sure to turn it with a garden fork every two weeks to aerate the pile and to move dry material from the outer edges to the center.

Compost has a dark crumbly texture

You’ll know when your compost is ready because it will look beautifully dark and crumbly, and should smell earthy. Still see an orange peel? It’s not done! You definitely should not be able to pick out any original ingredients.  If you don’t have the time or means to make compost yourself, give your township a call. Many municipalities compost the yard waste they collect and then offer the finished product back to their residents.

Hay: Not Just for Horses…

…it’s also for your garden! Here at Southern Exposure, we often use hay and straw to mulch our crops.

Hay comes from grasses and legumes such as alfalfa or clover that are cut, dried, and used to feed farm animals. Straw, on the other hand, has little to no nutritional value for animals–it is made from dried, mostly-hollow stalks of grain. Straw and hay make for different mulching experiences.

Hay Mulch

Hay is nice and heavy, so it is likely to stay put once placed in your garden. However, when mulching with hay, be aware that it could contain weed or grain seeds that may eventually sprout. This is not really an issue with straw, but straw is much lighter than hay, which means that you’ll have to use a lot more of it to get it to stick around come wind and rain.

Oak’s No Joke

Blueberries growing in oak leaf mulch

If you’re a fellow resident of Virginia, where live oaks are commonplace, you might want to try using oak leaves as mulch. Live oaks are classified as evergreens because they hold onto their leaves all winter long…but come springtime, keep your eyes peeled! You won’t have to look very hard to find fallen oak leaves in abundance, as live oaks drop their leaves over a two-week period each spring.

Oak leaves add acidity to soil, so make sure you’re using them on plants that can tolerate this. You can either directly mulch your garden with oak leaves, or compost them first (chopping them up with a lawn mower or other tool will help them to decompose faster, as will mixing them with nitrogen-rich materials).

The Electric Pine Needle Acid Test

Using pine needles as mulch, which is often called pine straw, is a good idea when you are looking to increase the acidity of your soil. Garlic, mint, onion, blueberry and tomato plants would appreciate this, as would azaleas, chrysanthemum, rhododendron, and roses.

And besides giving certain plants their acid fix, pine needles bind together to provide a weed-suppressing blanket that is unlikely to wash away with heavy rains.

Another great thing about using pine needles as mulch is that you can easily collect it yourself. Even if you don’t have pine trees on your property, neighbors with pines might happily agree to let you scoop needles off their grass—the needles’ high acidity makes for splotchy lawns!

Coulda Shoulda Wooda

Wood mulch is a common type of mulch because it’s good at suppressing weed growth. But if you’re planning on buying commercially produced wood mulch, be aware that it may be made out of trashed wood, which could add arsenic and other chemicals to your soil.

Wood chips for mulching a path

Also, if you want to avoid moldy mulch, using wood chips as mulch might not be the best choice. Now, some molds and fungi—natural aspects of the decomposition process for all organic material—are benign or even beneficial for plants. But others are nuisances. Case in point: wood mulch can breed a nasty mold called “shotgun” or “artillery” fungus, which leaves impossible-to-remove spores that look like balls of tar on homes and cars.

If you’re still into the idea of using wood mulch, why don’t you try sawdust? The founder of Southern Exposure originally used sawdust as mulch in his garden, and he had no problems with it.

Rubber Mulch: Old Tire Chunks on Your Plants?!

For instance, did you know that many types of mulch you can buy in the store are thickened with ground rubber, potentially from used tires? Though rubber mulch might be good for playgrounds (if you don’t mind exposing your kids to the chemicals components of artificial rubber, but hey—we’re not talking child rearing here), it simply does not belong in your garden.

The cons of using rubber as a mulch ingredient far outweigh the fact that rubber contains a small amount of nitrogen. Zinc, cadmium and other heavy metals from rubber mulch could seep into your soil. Plus, it stinks in the heat!

What’s Mulch Got To Do With It?

In conclusion, we just want to reiterate something you’ve hopefully already figured out—mulch is very important! All mulch types help soil and root health by retaining moisture, managing temperature, and preventing weed growth.

Finished compost