Container Gardening

 

Container Gardening: Anytime, Anywhere

Originally published June 1993

Container gardening offers many advantages that people can tend to overlook: containers can be less work because they can be placed closer to a water source; they offer a smaller soil area to have to weed; they can be placed at a height that can minimize bending for watering and tending; movable containers can “follow the sun” if you have changing exposure; they can provide a garden plot even in high-rise apartments or homes with no space for a traditional garden; and just about any plant—flower or vegetable—can be grown in a container.

Selecting a Container

Virtually anything that will hold soil and water is a candidate for container growing. From a bag of soil with holes punched for planting and drainage to wooden tubs, old riding boots, milk cans, hanging baskets and fancy ornamental pots. You can choose the size, shape and cost to fit your needs and desires.

The deeper the pot the less watering it will need. Pots with a small soil volume will dry out faster and require more frequent watering. Unlike plants in the ground, plants in pots or hanging baskets in the yard, on a deck or on a windowsill are exposed on all sides to the drying effects of wind and sun. On hot, windy days you may have to water them more than once.

Darker colored containers will absorb more heat, which can get seeds and transplants off to a faster start, but these containers will need more watering if they are in direct sunlight. Lighter colored containers may be better for most people.

Select a container that will give your plant’s roots room to grow, but not so much that it will not fill out the pot. Consider the mature size of the plants you will be growing, and follow the spacing recommendations on the seed packet or plant label. Plant leaves should grow to touch each other in a container, providing shade that will help retain moisture in the pot. Because weeding will be minimal and you can easily reach into a pot, there is no need to plant in rows and you can space plants closer together in a container than in a garden.

Plastic vs. Clay

While unglazed clay containers, such as those made of terra cotta, may seem more “natural” or appeal to those who want a certain look, plastic containers offer an advantage if they are to be placed in full sun. Unglazed clay pots are porous and water can quickly evaporate from them, while plastic containers do not “breathe” and therefore they will not need watering as often as clay. If you like the look of clay, there are look-alikes available in plastic.

Drainage is Important

Be sure that your container allows for drainage when you water. If the pot doesn’t have a drainage hole in the bottom, add one. If you don’t want to put a hole in a decorative ceramic container you can simply put a smaller pot inside the decorative one, being sure there is some room at the bottom for water to drain out. This will provide a reservoir for the water to drain into. The soil has to drain water or the plant roots won’t be able to breathe.

Soil Selection

Some people are tempted to just dig up some garden soil and put it in a container. Generally, though, you are better off buying a prepared soilless mix for container growing because it is free of weeds and often contains added nutrients to help plants grow. Choose a potting soil that will provide support for plants as they grow, and one that will help retain moisture. A peat and perlite or peat and vermiculite mixture is usually a good choice.

Planting Procedures

Thoroughly water the soil before planting. Water gently until water drains from the bottom of the pot. This way you can be assured that the entire soil mass is wet. If you are going to move the pots, you may want to move them before watering so they will not be as heavy as they will be after watering.

For seeds, follow the seed packet directions for spacing and whether or not to cover the seeds with soil. Keep the soil moist by gentle misting or watering several times a day. When seedlings emerge keep them watered, and if you have too many plants thin them by plucking out the weakest looking ones.

For transplants, plant the top of the root ball even with the soil line and keep plants well watered as they get established.

A simple test as to whether or not to water is to stick your finger into the top inch of soil. If it feels damp, there is no immediate need to water; if it feels dry then you should water until some runs out the bottom of the container.

Mulching Helps

Plants that will be grown outdoors in full sun in containers can benefit from a layer of mulch on top of the soil. Mulch will help retain moisture in the soil, discourage weed growth, and break the harshness of raindrops or watering from a hose or watering can. Sawdust, shredded bark and gravel can act as mulches—choose one appropriate to the container and the plants.

Containers placed in semi-shady or shady areas do not need mulch as much as those planted in full sun, but it is never a bad idea.

Staking Tall Plants

Vining plants such as tomatoes, cucumbers, morning glories, thunbergia and others will need the addition of stakes or a small trellis to support them. Add the stakes or trellis when you first plant the seeds or transplants so that you won’t damage roots by adding them at a later date.

When the plants are large enough that you need to fasten them to the stakes or trellis, do not tie the stem tightly to the stakes. Leave a big loop that will support the stem but not constrict it. For large-stemmed plants like tomatoes and melons, strips of cloth are gentler than plastic or metal twist-ties. When fruits begin to get large, a cloth sling tied around the fruit and fastened to the stake can keep the fruit from falling off before it is ripe.

Extending the Season

One of the special advantages of container growing is that you can extend the harvest or bloom season by moving pots indoors when the weather grows cold. When you move them indoors, put the containers in a location where they will receive maximum sunlight during the day. Eventually, winter’s shorter days will take their toll and your plants will get scraggly looking. You may want to finally get rid of them, but with the right exposure, you can keep plants growing indoors for months after their usual outdoor life.

Other Advantages of Containers

Growing in containers gives you an opportunity to try something new on a small scale. If you have a shady area that you want to test to see how certain plants will grow, putting a few in a pot in that area will let you see how they do without a lot of work. Of course, you can do the same for sunny locations too. By grouping several pots, each with a different selection, you can see which ones do better so that you can decide what to grow more of next year.

Container growing is also an excellent choice for introducing children to gardening. Containers are easy to tend and can be sized to the age and interest of a child. A child’s favorite vegetable or cutting flowers are popular choices to get them started.