When grown in location with lots of sun, herbs will tend to produce more harvestable leaves and flowers. Container gardens, on the other hand, prefer a location with late afternoon and evening shade. In order to encourage the use of your herbs in cooking or garnishing, it's best to locate your container garden near a source of water and close to the kitchen.
Choosing the Proper Size Container
When herbs reach their maturity, their root systems will be a little larger than their top growth. It is important, then, to pick a container that is big enough to allow space for the roots to grow. Of course, herbs will vary in size so a good rule of thumb is to allow 1 gallon of potting soil mix. For instance, a 12-inch pot contains about 3 1/2 gallons of potting soil mix, so it will be able to hold about 3 to 4 herb plants. A 16-inch pot can hold about 5 1/2 gallons of potting soil, so it can hold about 5 or 6 herb plants. Whatever type or size of pot you use, make sure it has good drainage holes. Choosing the Right Potting Soil Mixture
Container grown herbs will grow best in a good quality potting mix or "growing medium" as opposed to trying to grow them in real soil. Potting mix tends to be sterile, retains moisture well, and allows for good aeration for your plants. A good mix will contain sphagnum peat moss, perlite or vermiculite, and even sand or fine pine bark. Most potting mixes you'll find will contain no fertilizer. You can mix either a granular complete fertilizer with a trace element-type fertilizer into your chosen potting soil mix before planting, or you can use a soluble complete fertilizer after planting. Whatever fertilizer you decide on, use a low application rate fertilizer to enhance the herbal flavor and aroma of your plants.
Choosing the Right Herbs for Your Container Garden
Some types of herbs will out-perform others in containers. It's best to choose herbs that tend to be compact and grow low to the soil. Tall herbs, dill and fennel for instance, may look too large compared to the size of the pot, and the increased weight may cause the container to tip over. Drought-resistant herbs are a good choice for containers in case the container accidentally misses a watering or a particularly hot, sunny day causes the water to evaporate faster than expected. Herbs with trailing foliage are pleasingly attractive in container gardens as they drape and cascade over the sides of the pot.
Planting Your Container Herb Garden
When attempting to pot transplanted herbs, it's important to plant them at the correct depth. The top of the transplanted herbs root ball should be level or slightly below the potting mix surface in the new pot. When transplanting from several pots of varying size, you need to adjust the plant depth accordingly, as each plant will have different size root balls. Begin your planting with a moist, not saturated, potting mix. As you are adding moisture to your potting soil, keep in mind that most mixes wet more easily when using warm water. Add your moistened potting soil mix into your container until the top surface of the tallest transplant root ball sits about 3/4 of an inch below the container's rim. Continue to add potting soil mix and transplanted plants until the container is filled to within 3/4 of an inch from the top edge of the container.<i> Do not pack down the soil as you fill the pot.</i> Once filled, water the container thoroughly, until you see water dripping through the drainage holes.</p>
Caring for and Harvesting Your Container Garden
Perhaps the most common problem in caring for container herb gardens is watering - either too much or too little. Watering your container garden too often can lead to fungal infestation, fungus gnats, and root rot. Some to the signs that you are over-watering include wiliting, fungus gnats, reduced root growth and wilting. Watering too little will lead most often to wilting and scorching. If under-watering continues for too long, the repeated wilting this causes will stunt the growth of the plants and reduce their flower quality. The best procedure to ensure proper watering is to add enough water until it runs through the bottom of the pot. You should water your container herb garden only when needed. Feel the potting mix about 2 to 3 inches below the surface to gauge if it needs watering or not. If the soil is still wet, don't water.
Another way to decide if you need to water or not is to gently tip the container to determine its weight. When the container begins to feel much lighter than usual, it's time to water again. When your plants are first planted and small in size, they use less water and may only need watering as little as every 5 to 6 days. During the summer, when your plants have grown and matured, their roots will have grown throughout the pot and you may need to water as often as every day.
If you mixed a slow-release fertilizer inot your potting soil, you should not need to fertilize your plants for 2 months. If no fertilizer was added when you planted your container herb garden, use a soluble complete ferilizer at the rate of every third or fourth watering. It's important in any container herb gardening to control pests that may harm your plants. Herbs are generally pest-resistant, but watch out for aphids, spiders mites, and caterpillars. Use a less toxic insecticidal soap instead of an insecticide to control pests, especially if you plan on consuming the leaves of your herb plants. One teaspoon of liquid soap (not detergent), applied with a sprayer will get rid of aphids and spider mites. This type of organic pest control must be re-applied every 3 to 4 days until the pests are gone.
To keep your herbs growth under control, it's best to harvest your herbs on a regular basis as this will increase the production of your herbs. Harvest your herbs on a dry morning, after the morning's dew has dried. For best flavor and aroma, use your herbs fresh, or they can be preserved by drying or freezing. At the end of the growing season, you can save some of the more tender perennials, such as marjoram or rosemary, by bringing them into the home. The best way for indoor herb container gardening is to place your container plants in a sunny window, or give them some artificial light for up to fourteen hours per day. Water them like you would any other houseplant. In order to protect perennials in the winter, plant them in the ground next to the south wall of your home or the south side of a stone wall to shield them from the cold winter weather. Apply mulch around the herbs to a depth of 6 to 8 inches. Winter gardening herbs outside still may need watering, especially during a dry winter.