Marin IJ Articles
August 4, 2018
Container gardening has exploded in popularity in recent years. Who doesn’t love those gorgeous potted bouquets featured in home and garden magazines?
You can grow almost anything in containers, from colorful ornamentals to vegetables, herbs, and small trees. Pots make gardening possible on balconies and rooftops, in small spaces and in places where soil is poor. They have the advantage of portability and can be moved from time to time to avoid frost or scorching sun or to show off the prettiest seasonal blooms.
But be aware that plants in pots need more care than those in the ground, and they are completely dependent on you. They need more frequent watering and feeding, and they are more vulnerable to temperature extremes.
A successful container garden starts with selecting plants that will thrive in the spot you have in mind. Consider sun, water needs and special conditions, such as wind or intense heat. Then it’s time to pick a pot. Choose one large enough to support the plant and its root system for several years. A grouping of plants will require enough room for growth for all.
Containers may be ceramic, clay, wood, plastic, fiberglass or almost any material as long as there are drainage holes. Clay pots dry out quickly and work well for plants such as succulents that like dry conditions. Plants that need continual moisture are usually happier in a glazed or plastic pot. Place window screen over drainage holes to retain soil, and keep the potting mixture an inch or two below the rim for water absorption.
For most containers, it is important to use potting soil, not soil from the garden. The exception is for sizable trees or shrubs, when a mixture including some garden soil adds weight and stability. “Potting soil” is actually a soilless mix, often of peat moss, bark and perlite or vermiculite, formulated to drain quickly yet retain moisture. You can buy prepared mixtures or make your own. Potting soil combined with up to one-third compost is ideal for many plants. “Cactus” mixes are available for succulents and others that require excellent drainage.
Regular maintenance, including watering, feeding, grooming, and repotting is critical. How much water your containers need depends entirely on plant types, the size and porousness of pots, weather and location (sun or shade). Small pots, clay pots and those in full sun may need daily watering, particularly in mid-summer. A drip system is handy if you have many containers or like to travel.
Too much water is as harmful as too little and the demise of many plants. The best guide is to stick your finger in the soil, and if the top inch or two is dry, give them a drink. Water thoroughly, until a small amount seeps through drainage holes. If pots drain too quickly or feel light, they may have completely dried out and can be remoistened by placing them in a bucket of water for several hours.
Fertilize regularly, every two to four weeks, during the growing season. Most potting soils are low in nutrients and lose them quickly through drainage. Organic fertilizers include compost, seaweed and fish emulsion. Inorganic varieties come in liquid, granular or slow-release forms.
Grooming keeps containers looking their best. Deadhead faded flowers to encourage repeat blooming, and remove a few plants if they become overcrowded. Rotate pots for even growth, and pinch back leggy shoots. Keep an eye out for pests and diseases.
Container plants need to be repotted every few years as they become root-bound and potting medium breaks down. Remove the plants, then gently loosen roots and cut back any that are coiled inside the pot. Replant using fresh soil and a container that is a few sizes bigger. Mature plants in large pots may be “root pruned,” removing up to one third of the roots, and replaced in the original pot with new soil.