There is nothing like enjoying the warm spring breeze and the sweet aroma of one of your favorite herbs in your garden. You have just pulled away some fresh, warm sprouts of mint or basil from a pot in your kitchen!
While you might have grown herb plants before, you might be unsure which type of soil is best to grow them in. If you are interested in improving your current recipe for growing herbs, read on to learn more about selecting the best soils for growing herbs.
Keeping an herb garden at home presents a wide range of culinary possibilities. Fresh herbs can be expensive in the supermarket, but those grown on the windowsill or on the porch are equally flavorful at a fraction of the cost. Proper soil and planting conditions of your own herbs will ensure healthy herbs which provide ample seasonings and garnishes.
Soil Types For Your Garden Area
Most herbs do best in well-drained soil. If your natural good soil is heavy clay, cracked pea gravel or a coarse compost mix can improve drainage so the roots of the herbs do not drown in too much moisture.
A layer of crushed stone placed at a depth of about 18 inches beneath the herb raised bed also will improve good drainage in heavy soils. For sandy soils, a bit of rich compost will improve water retention just enough to make herbs comfortable. A soil pH level between 6 and 7 is generally best for the best herbs garden.
Soil Ph Of Your Outdoor Garden
Garden soil with a pH between 6.3 and 6.8 provides the preferred growing conditions for most herbs. Soil pH measures the acidity level in the soil. A soil test kit determines the pH level and indicates if amending the soil to improve pH is necessary.
Beds with improper pH levels typically require an application of agricultural lime to bring the pH levels into the best growing range. Established beds where vegetable young plants have previously grown usually already have the proper pH level.
Soil Moisture And Regular Watering
While many herbs are drought tolerant, they still grow best in soils that provide adequate moisture. Sandy soils dry out quickly since moisture from irrigation quickly drains from the bed. Clay soils collect too much water in the soil or they compact so that moisture builds up on top of the soil, which leads to root suffocation and rot problems.
Soils rich in organic matter drain sufficiently so they don’t become soggy but they also retain enough water to remain moist. Amendments such as compost helps improve the moisture qualities of poor soils.
Bed Preparation For Outdoor Herbs
Herb plants establish quickly in loose, well-worked soils. Working the soil also provides aeration to the roots and ensures moisture penetrates into the soil well. An addition of compost and the lime amount indicated by the soil test occurs before working the soil.
These amendments are turned into the top 8 inches of soil with a tiller or spade. Removal of any rocks or large roots uncovered while tilling ensures this debris doesn’t inhibit root formation on the herb plants.
Fertility Of The Right Potting Soil
Culinary herbs typically don’t require highly fertile soils to grow well, and some plants may fail to produce their flavorful oils in highly fertile locations. Beds that have a high organic matter content may require no fertilization if you only grow annual herbs.
Beds with lower fertility levels or those that are home to perennial herbs do require some supplemental fertilization. A light application of a balanced fertilizer at half the package-recommended rate for vegetables at mid-season generally supplies enough nutrients to the soil.
Herbs need little if any, fertilizer to do well. Slow-release fertilizer pellets for fertile soil can be added to new container herbs to get them established. A little organic matter such as compost can help. Herbs typically respond poorly to manure dry soil.
A mulch of 1 to 2 inches of composted bark will keep down weeds and warm the soil structure. For woody herbs that are especially sensitive to moisture, a mulch of gravel can protect the roots from too much moisture.
Most flavorful herbs prefer about six hours of direct sunlight. Many tolerate partial shade but most do poorly in total shade. In sunny climates, herbs can be grown year around on windowsills provided they get enough sunlight.
Herbs are a popular choice for container gardening, where they do well in two parts well-drained right soil mixed with one part coarse sand.
Watering For Plant Growth
Different herbs are very sensitive to overwatering. Allow the soil to dry out between waterings; the indoor herb garden plants should never be drenched. Established new plants growing outdoors will require very little watering if you live in an area with occasional rains.
Established herbs indoors will benefit from occasional misting and light watering when the soil becomes dry.
The Best Soil Mix For Herbs For Container Gardening
For less than the price of a bundle of fresh herbs at the supermarket, you can grow your own supply. A single window box on a sunny sill or porch is all you need to grow a variety of herbs. The right growing medium can be the key to your success when growing herbs in containers.
Soil-less growing mediums are popular for potted plants, but soil-based mixtures are better for container gardening, according to the Arizona Cooperative Extension Master Gardener Manual.
Soil provides a more constant stream of nutrients to herbs. Herbs that lack those nutrients are less flavorful and aromatic. Never dig up ground soil for a potting soil mix when growing herbs, as the clay content can compact roots and reduce aeration, and microscopic organisms can infect plants.
Instead, use a sterilized loam. Loam is the perfect soil blend, containing a balanced amount of clay, sand, and organic matter. If loam is not available, topsoil from a garden center will suffice, but for best results be certain it is sterile. A potting soil mixture should consist of at least one-third of the soil.
The second component for a potting mix should be partially decayed organic matter that is lightweight and will aerate your mixture so it holds water, oxygen, and nutrients well. Peat is the best candidate as it takes a long time to decompose.
There are different types of peat, made from different types of vegetation and existing in various stages of decomposition, and the National Sustainable Agriculture Information Service warns that each will have different results in a soil mixture.
For potted herbs, sphagnum peat moss is highly recommended because it is less decomposed than most peat, and therefore more stable. One-third of your growing medium should be organic matter.
An alternative to peat is a mixture of Perlite and vermiculite, which are volcanic minerals. These are not as effective as peat moss in retaining nutrients in the pot but can replace peat if necessary.
Sandy Soil For Growing Season
The third and final essential component of a good potting soil mix is one-third sand. Sand helps improve drainage in the pot, and since humus is so light, the weight of the sand can help anchor the pot better.
The best type of sand to use is clean, coarse sand, recommends the American Horticultural Society, such as builder’s sand. Use gravel as an alternative to sand if desired. Beware of using fine sand, which can become compact and impede drainage.
Aside from soil, peat, and sand, there are other optional elements you can add to a potting soil mixture in order to improve the quality. Since peat moss can be acidic, you can bring a better balance to your mixture if you use it by adding one tsp. of dolomitic lime per gallon of potting mix.
Compost, at approximately one-half cup per gallon of soil mix, can provide additional nutrients. If your region is dry or hot, you might save the life of your herbs by blending polymer water crystals with the potting mixture. Finally, time-release fertilizers can continuously feed your herbs for up to six months.
The amount you need of polymer water crystals and time-released fertilizer will depend upon the size of the containers you use, so follow the guidelines on the packaging.
Herb Garden Options
Basil, mint, thyme, and rosemary are just a few herbs that grow well in most outdoor herb gardens. Herb plants require little maintenance and are tolerant of most garden conditions, including shady plots and beds with low fertility. Preparing the soil before you plant improves the health of the herbs and helps them remain productive as they reach maturity.
So there you have it, a brief guide to better herb growing. We’ve covered a lot of ground in this article, from general things to consider when you’re choosing a spot for your herb garden, to more specific details about the variables involved in soil preparation, types of compost and materials to avoid.
Hopefully it’s given you some good ideas and suggestions as you prepare your own herb garden space. If you have any questions about growing herbs that are not answered here, please feel free to get in touch and we will do our best to help.