Soil – Maryland Grows

How to adapt your garden to climate change

August 26, 2022August 25, 2022Maryland Grows1 Comment

The news is filled with references to global warming and climate change. In fact, 99% of scientists agree that climate change is real with negative impacts on the environment, weather, human health, and agriculture. In Maryland, climate change is already causing higher average temperatures, more drought, longer heat waves, more intense storms, and flooding.

So what can we do as gardeners to help the cause and help our gardens adapt to these changes?

Adopt sustainable practices. Environmentally smart practices build climate-resilient gardens and can slow future warming by reducing emissions and boosting carbon in soil and plants. Here are a few ways to get started:

Plant more trees

Trees filter air and water and are carbon sinks, capturing and storing carbon dioxide, a key greenhouse gas. When placed well, trees can save up to 30 percent on heating and cooling costs.

Plant deciduous trees on the west, east or southwest side of your home to block summer sun then let it in to warm your home in winter. Site evergreens to the northwest to buffer winter winds.
Lean toward native trees. They’re well-adapted and need less water and fertilizer, the manufacture of which can contribute to greenhouse gases.

Add or nurture native plants

Native plants such as this chokeberry and golden ragwort support wildlife and build climate resilience.

Don’t stop with trees. Native shrubs, perennials, grasses, and groundcovers also help build a climate-resilient landscape. Native plants, once established, require less water and fertilizer, help store carbon, and reduce soil erosion. Since they co-evolved, native plants best support native pollinators and beneficial insects which provide chemical-free pest control.

HGIC Website: Native Plants and Climate Change

Keep it diverse

Plant diversity also boosts resistance to pests and disease, so add many different types of plants to your gardens. Yes, more is better.

Save the soil

Washington County Master Gardener Gary Stallings turns compost, a tool in building soil health and climate resilience

Great gardens grow from the ground up. So protect and improve your soil which stores massive amounts of carbon as carbon dioxide and organic matter.

Keep soil covered since bare soil invites problems. Soil covered with plants, mulch, or cover crops best stores carbon, resists erosion, holds moisture, and has more even temperatures.
Minimize soil disturbance from digging and tilling which speeds up the loss of organic matter and disturbs the soil community.
Recycle nutrients by making and using compost. Compost adds organic matter, helps soil hold water and nutrients, and reduces the need for fertilizers.

HGIC Website: Improve Soil Health for a Climate-Resilient Garden

Water wisely

Save water to make your garden more climate-resilient. Use a rain barrel or create a rain garden to capture and filter rainwater.
Water when plants need it, not on a fixed schedule. And plant in the spring or fall when plants need less water to become established.

A few more tips:

Limit the emissions that contribute to greenhouse gases. Use gas-powered mowers, trimmers, and other equipment less and opt for alternatives.
Shrink your lawn and replace it with groundcovers and other alternatives which need less water, mowing, herbicides, and fertilizer. When you do fertilize, do it based on a soil test to use only what you need.
Help more by growing some of your own food or supporting local growers to cut down on emissions from long-distance transportation.

You can make your garden more climate-resilient. Start with a few steps and build on them to help your garden successfully adapt to climate change.

By Annette Cormany, Principal Agent Associate and Master Gardener Coordinator, Washington County, University of Maryland Extension. This article was previously published by Herald-Mail Media. Read more by Annette.

This article was previously published by Herald-Mail Media.

What is so special about legumes?

August 24, 2022August 30, 2022Maryland GrowsLeave a comment

a collage of three photos shows alfalfa plants growing in a high tunnel — Alfalfa (a legume) with nasturtium growing at the edge of a high tunnel. Photo: A. Bodkins

There is a whole group of plants in the Leguminosae (a.k.a Fabaceae) plant family and are referred to as legumes, a word that many people may have heard but may not know the special details about. Have you ever heard that legumes make their own nitrogen or that they are plants that never need nitrogen fertilizer? Well, both those statements are true!

Continue reading →

How can you improve your soil?

July 27, 2022July 27, 2022Maryland Grows2 Comments

a sloping landscape partially planted with cover crops — *A cover crop of spring seeded oats is included on this slope with grass and trees. Photo: A. Bodkins*

Healthy soil can sustain plant growth, prevent environmental damage, mitigate stormwater runoff, and help recharge and clean groundwater.

Soil type is probably not something that people consider when they move to a new property, so it reminds me of the statement “you get what you get and you don’t throw a fit”. However, it is no secret that soils are not all created equally in their ability to grow plants. To make matters worse, the soil is constantly being manipulated to accommodate our needs. When infrastructure like roads and buildings are constructed soil is moved and in many instances, there may not be any native soil profiles still intact on the property. Often a small layer of topsoil is put back onto the landscape after construction and regrading of the land, but there is no guarantee that it was the topsoil found there before construction began. Once the excavation is completed there is no going back. This article from Penn State Extension, Can Disturbed Soils Grow Healthy Landscape? is a great read. If you suspect that the soil you are planting vegetables into has been hauled in from another location, it is wise to get the soil tested for lead content. Some labs also test for heavy metals like arsenic (As), cadmium (Cd), and chromium (Cr), which can be found in soils on old industrial sites.

Soil is the gift that can keep giving, but there are some management practices that can help improve all soils. The physical, chemical and biological processes of soil are all interconnected. If you want to learn more about your own soil, I recommend the Kansas State publication that walks you through the steps to Estimate Soil Texture by Feel. Knowing the soil texture in your garden is one piece of the soil puzzle.

Soil organic matter increases water holding capacity, improves water infiltration, serves as a source of micro and macronutrients, and provides large particles for micro and macroorganisms to break down. Soils that are high in clay or sand can benefit from the addition of organic matter, which comes from anything that was once alive. Macro and microorganisms help to break down organic matter and release nutrients into the soil. There are many forms of organic matter that include compost, plant material, livestock waste, humus or leaf litter.

dark soil is rich in organic matter — *A cross-section of healthy soil. Photo: USDA*

Cover crops are another way to improve your soil because they capture excess nutrients that are left over from the growing season and prevent the nutrients from becoming environmental pollutants. Cover crops also prevent soil erosion from wind and rain during the late fall, winter, and early spring seasons when weather is not appropriate for most vegetable or agricultural crops. Once cover crops are terminated they can be plowed into the soil and add organic matter. This is called green manure. I’ve found that in my own garden, cover crops can also help prevent weeds from growing. Some cover crops like forage radishes die and create natural pathways through the soil for water to flow.

buckwheat cover crop planted over a vegetable garden soil — Buckwheat that I planted as an early season spring crop to help reduce weed germination in my vegetable garden. I had planned to terminate it and plant a late crop of cucurbits, but changed my mind after it was growing so beautifully and I saw all the insects that were visiting it daily.

Other management practices to help your soil include regular soil testing to monitor any changes and keep the soil pH in the correct range for your desired plants. Limit soil compaction by keeping vehicles, equipment, and even people from walking through gardens, especially when the soil is wet. At the very least, I think the best practice for improving and keeping your soil healthy is to leave it alone as much as possible, keep it covered with plants that are not invasive, and let the natural processes of the Earth work together to benefit the soil.

By Ashley Bodkins, Senior Agent Associate and Master Gardener Coordinator, Garrett County, Maryland. Read more posts by Ashley.

This year, the University of Maryland Extension Master Gardener Grow It Eat It Program celebrates the resource that supports all life on earth – soil! Look for soil education programs offered by your local Master Gardener program, and visit the Home & Garden Information Center website for more information about soil health.

did you know soil is a natural resource and a living ecosystem

Do plants get food from the soil?

June 22, 2022June 17, 2022Maryland GrowsLeave a comment

cabbage plant — Cabbage. Photo: A. Bodkins

People often say you have to feed your plants, but in reality plants make their own food through the process of photosynthesis, which yields oxygen and glucose. Glucose is the food that plants use for energy and growth, they don’t need us to actually feed them. Since plants can make their own food, they are called autotrophs. The green pigments in plants, called chlorophyll, capture light energy from the sun. The process isn’t nearly as simple as I’ve described it.

Plants can further be divided into two classifications, C3 or C4, which is determined based on how efficiently the plant can photosynthesize and whether the plant has to go through the process of photorespiration, which is required for C3 plants. This makes C4 plants, like corn, sorghum and sugarcane more drought resistant because of the complex processes that occur within the plant at molecular levels. The majority of plants are C3 plants. For more information on this topic check out the article from University of Illinois, The difference between C3 and C4 plants.

So why do plants need a soil that is sufficient in macronutrients and micronutrients if that is not their food? Well, the short answer is that nutrients help plants grow and keep them healthy so that they can photosynthesize efficiently. As the plant mass increases, the plant leaf size/surface area increases, which allows the plant to capture more sunlight and turn it into more food.

You can check out the Home and Garden Information Center’s webpage about fertilizer to learn more about macronutrients and micronutrients. Macronutrients are those elements that the plant needs the most of to be healthy. Water provides hydrogen and oxygen. Carbon dioxide provides oxygen and carbon which are part of the required macronutrients for all plants. The remaining macronutrients are provided by soil (unless the plant is being grown hydroponically, of course). Plants can only take up or use nutrients that are dissolved in soil water. This is why it is so important to make sure that your soil gets sufficient water. Some plants are called heavy feeders and this is generally in relation to their need for larger amounts of the macronutrients, especially nitrogen. Some examples are tomatoes, everything in the cabbage family, and beets. The University of Maryland provides more information on fertilizing vegetables.

tomato plant — Tomatoes (left) and a colorful cauliflower harvest with nasturtiums (right). Photos: A. Bodkins

yellow and purple cauliflower plants — Tomatoes (left) and a colorful cauliflower harvest with nasturtiums (right). Photos: A. Bodkins

By providing an optimum growing environment, through correct amounts of light, moisture, and nutrients, the plant will have the best chance at reaching its full potential. As I eagerly wait for the first produce from my vegetable garden this season, I want to be sure that all my plants reach their full potential and produce a large amount of food for me and my family to enjoy this growing season.

Please comment below with what you are doing this year to ensure that your plants are healthy and happy and growing well. Do you test your soil every 3 years or whenever you are planting a garden in a new area? Do you research the plant needs (full sun, part sun, or shade) before planting? What questions do you have about managing soil fertility and nutrients?

By Ashley Bodkins, Senior Agent Associate and Master Gardener Coordinator, Garrett County, Maryland. Read more posts by Ashley.

What is soil pH and does it really matter to plants?

May 25, 2022May 25, 2022Maryland Grows3 Comments

Well, the short answer from a soil nerd (please note soil nerd is not the same as a soil scientist or soil chemist) is that yes it really does matter! Have you ever done the experiment with boiling red cabbage leaves and used that as a pH indicator? It’s a fun science experiment but probably wouldn’t work for determining an accurate soil pH.

People do not always see the benefit of getting their soil tested; however, if you take a good comprehensive soil sample, the information that you get from the analysis is invaluable. Not only will the results keep you from over-applying nutrients, which has economic and environmental benefits, but also it will ensure that your plants have all that they need right at their root tips.

In my opinion, the most helpful piece of information gained from conducting a soil analysis is the soil pH. PH is a measure of hydrogen ion concentration and tells you how acidic or basic/alkaline the soil is. Most vegetable garden plants prefer a pH between 6-7; therefore, acidic soils need to be amended with calcium carbonate (limestone). Acidic soils are indicated with numbers below 6 on the pH scale which ranges from 0 to 14. Soils in the Eastern US are often acidic, but the natural pH will depend on parent material and other soil factors, such as how the soil has been managed, what plants are growing there, etc.

It should be noted that some plants actually prefer acidic soils, such as rhododendron, azaleas, and blueberries. Also, some plant diseases, such as scab in potatoes, are worse at a higher pH. Lowering soil pH (often done by adding sulfur) can take several months and may need to be a multi-step process. It is a great idea to test garden soils in the fall, so pH-altering amendments have time to do their job. Here is a great cheat sheet to help you understand what your soil analysis results mean.

tomato plant with yellowing leaves on the bottom portion — Blueberry. Photo: C. Carignan

Another reason that pH is important is that it helps determine the availability of soil nutrients. Soil pH is linked to Cation Exchange Capacity (CEC), which is influenced by soil particle size and the type of parent material (rock). Clay soils will have a higher CEC (sites to hold onto nutrient ions) than sandy soils. CEC will be reported on most soil analyses. If the pH is not in the correct range, then many nutrients are not available to plants, even if you have applied ample nutrients. Thus, in order for the nutrients to support plant growth, it’s important to get that pH correct! This will provide both economic and environmental savings. Check out this link for a neat chart showing nutrients available and pH.

The third reason that it is important to check pH is because it can affect soil microorganisms, which are going to thrive at a near neutral level. If the pH is too high or too low you will see a decrease in the number and activity of good soil bacteria, fungus, and more that help to break down organic matter and do amazing other things in the soil profile. (For more details on this topic, download PDF – Soil Acidity Impacts Beneficial Soil Microorganisms, from Washington State University Extension.)

Common questions about soil pH

Can pH change from year to year?

Some forms of nutrients —commercial fertilizers, compost, composted animal waste (cow, horse, pig, chicken manure), organic matter, the weathering of rocks, and even rainfall can alter pH. Fertilizers, depending on the type used, will alter soil pH at different rates. Refer to this PDF – Fertilizers and Soil pH from the University of California.

Can I use a home soil Testing kit?

I normally steer people away from these types of kits, just because there are so many inaccuracies, especially, if the kits were not stored at the proper temperature and the directions are not followed correctly, then the results may not be 100% accurate.

What about electronic soil testing probes?

I don’t have first-hand experience with these probes. I am sure that they do have a level of accuracy; however, I cannot justify the upfront cost. For most gardeners, soil testing every 3 years is sufficient, so in my opinion, it is easier to just collect the sample and send it to a laboratory.

By Ashley Bodkins, Senior Agent Associate and Master Gardener Coordinator, Garrett County, Maryland, edited by Christa Carignan, Coordinator, Home & Garden Information Center, University of Maryland Extension. See more posts by Ashley and Christa.

Are you looking at my soil?

April 27, 2022May 11, 2022Maryland Grows1 Comment

As a first-year college student studying horticulture (and later agronomy) I had no idea what I was in for when I signed up for that first Introduction to Soil Science course. Growing up, gardening and working on my family’s dairy farm, soil was something that we often talked about, mainly if it was wet or dry, rocky or smooth, and of course to stay out of the garden when it was wet; however, I really didn’t understand how important managing it was or how many different parts could be studied!

The technical definition of soil is the natural body composed of solids, liquids, gasses, and living matter that is capable of supporting plant life and has properties resulting from the five factors of soil formation. Wow! A mouthful of words, but a key point from this definition is the word NATURAL— soil is what covers the earth naturally and helps to absorb and disperse solar radiation and precipitation. It also provides an anchor for plant life. With harsh treatment, this living portion can be damaged and thus can take many years to build back. It is important to know too that healthy soils help to mitigate climate change as they store a huge amount of carbon in the form of carbon dioxide (CO2) and organic matter.

Continue reading →

Improve Soil Health for a Climate-Resilient Garden

April 15, 2022April 21, 2022Maryland Grows1 Comment

Soils, plants, and animals are highly interdependent. Soils support and feed microbes and plants which feed animals. Dead plants and soil critters replenish the soils’ organic matter and nutrient supply, completing the cycle. We know that healthy soils produce healthy plants. Many experts believe that improving soil health is the most important thing we can do to make our farms and gardens more climate-resilient.

Why are soils so important in dealing with climate change?

They store huge amounts of carbon in the form of carbon dioxide (CO₂) and organic matter, all of the living, dead, and decomposing plants, microbes, and animals that live in soil. Carbon dioxide is the primary greenhouse gas that is warming the planet. Deforestation, the removal of wetlands and peatlands, and soil tillage cause the release of huge amounts of CO_2.Warmer temperatures cause more rapid organic matter decomposition and turnover, especially if soils are tilled and uncovered.
Climate change is causing mid-Atlantic weather to be warmer and wetter with more extreme weather events, including periodic drought. This increases the risk of soil erosion and nutrient run-off from intense rainfall, and the risk of plant stress from excessively wet or dry soils.

Soil from a landscaping project that moved off-site in 2018. Maryland averaged 73 inches of rain that year!

Continue reading →