This article was originally published in April of 2018 but has been updated to include relevant content.
A garden needs a few things to thrive: water, sunlight, and ample room to grow, to name a few. Soil moisture, which goes hand-in-hand with proper watering, is another crucial component of keeping flowers, plants, and vegetables healthy.
What Is Soil Moisture?
Soil moisture is the amount of water that is captured and stored within the soil and is greatly dependent on precipitation (rainfall), temperature, humidity, and soil type. Whether concerning your lawn soil or your garden soil, stated simply, the soil moisture content can generally be referred to as the dryness of your soil.
Why Is Soil Moisture Important?
Knowing your soil moisture content is crucial for all gardens, lawns, and landscapes because different plants, soil types, and climates require different moisture content levels to thrive. If you pay close attention to your ideal soil moisture, then you can adjust your watering cycles and drip irrigation appropriately. In regions prone to drought, this can positively impact the environment (and your wallet, too!) by reducing your household water consumption, which reduces your water bill!
3 Types of Soil and Watering Information
Different types of soil can exist in many different regions and climates. Let’s take a look at the characteristics of various soil types and the amount of watering they require:
1.) Loam Soil
Loam soil retains moisture well, making it the optimal soil type for thriving gardens and can be watered normally. Identify loam soil by its color and texture: it has a darker brown or black shade and is crumbly to the touch but still holds water well. Garden flowers and plants grow best in loam soil.
2.) Sandy Soil
Sandy soil drains quickly, so it requires slow watering to thoroughly saturate soil root zones. To distinguish sandy soil from other soil types, it is usually light brown in color with a gritty texture. Because of this porous characteristic, it is not ideal for seedlings as water drains away quickly.
3.) Clay Soil
Clay soil holds more water than other types of soil but is slow to absorb and release the moisture. It is not recommended to over-water or water faster than the clay can absorb. Clay soil is characterized by its small particles and texture. When wet, clay soil is sticky to the touch but feels smooth when dry. Due to its high water capacity, it is often considered a heavier soil, and less commonly known is that clay soil can also take longer to warm up in the spring.
General Soil Moisture Information & Tips
No matter which type of soil you are using, these general tips can help:
- If you have sandy or heavy clay soils and would like to improve water retention, add compost or organic matter to your soil.
- Adding sand to clay soils or clay to sandy soils will create a cement-like soil, making water retention worse.
- One inch of water per week is adequate for most plants. You may use a basic analog rain gauge to track your weekly rainfall.
- If you want to quickly check soil moisture, insert a garden trowel or a wooden dowel into the ground. This can also show you the depth of the moisture.
Recommended Soil Moisture Levels
The plants listed in this guide represent commonly found species. Consult a local horticulture professional for more specific details on plants not found on this list. It is important to note that the majority of flowers, trees, and shrubs require moisture levels between 21% - 40%, while all vegetables require soil moisture between 41% and 80%.
NOTE: All vegetables require soil moisture between 41% - 80%.
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AcuRite Solution: AcuRite Smart Garden Monitoring
Monitor your garden soil moisture with real-time rainfall data measured right in your backyard. From digital rain gauges with storm alerts to complete garden weather stations with Wi-Fi connectivity, AcuRite offers all the wireless weather monitoring products to help you improve your garden health. With daily reports rainfall accumulation, you can adjust your watering cycle and irrigation system to maintain ideal moisture levels for your plants, as described in the charts above. Overwatering is the most detrimental to plants, so make sure your indoor and outdoor plants remain at the optimal moisture level year-round. Also, use this handy guide to further examine soil nutrients or this article to learn more about best soil conditions for your plants.
What’s your ideal soil moisture for your plants? Have you found one specific type of plant to be more or less sensitive to changes in soil moisture? How do you maintain your optimal soil conditions for your garden? Share your garden success stories in the comments below!