Torture time for plants in containers

Dracula was real.

Seriously. He was no vampire but a sadistic Wallachian prince known as Vlad the Impaler. His surname was Dracul, son of the devil. Myths were loosely based on his impaling exploits, as well as those of another nut named Countess Elizabeth Bathory, who liked to bath in human blood to keep her good looks. Medieval times were no picnic.

I think my container plants feel tortured, especially this time of the year. My April enthusiasm never makes it through the summer. August is when they need me most and, to be perfectly honest, I just haven't been there for them. I take no joy in it.

Containers

Clay pots are old school and not quite as common as they once were. They are porous and tend to dry out fast. Ceramic pots are the most expensive, ornate and breakable. Plastic pots can look a lot like ceramic nowadays, and they're much cheaper. Regardless of the material they're made of, be sure containers have drain holes. Excess water is the sure way to kill plants.

With regards to pots, size does matter. Small pots become root-bound and dry out quickly. If you're growing vegetables, who cares what the container looks like? Just make sure it's big enough to accommodate large plants.

Soil

Filling pots with soil from the backyard will be too heavy and wet. Potting soil should drain well while holding available water.

Most store-bought brands are suitable for homeowners. There are numerous brands available, some containing fertility or water gel polymers.

Soil contains decaying organic matter. Many professionals use soilless potting mix, such as Pro-Mix, that contains peat moss, vermiculite and perlite because of its exceptional porosity and water-holding capacity. It is also sterile, reducing the chances of disease. However, because soilless mixes have no organic matter, they lack nutrients and require fertilizer.

Water

Keeping plants watered gets more difficult throughout the growing season because a) it's hotter, b) plants are bigger, and c) more roots clog the pot.

Ideal root growth will occupy two-thirds of the pot. Repotting is not necessary if plants can be watered every two days. Root-bound plants become so tight that soil is difficult to wet. Put a potato vine in a window box and see what happens.

There's no pat answer to how often you need to water because there are so many variables. Overwatering, however, is as bad as underwatering.

There are several water gauges that can be inserted in the soil to tell you when to water, but there's nothing like sticking your finger in the soil to see if it's dry.

Water gel polymers are crystal granules that hold about 400 times their weight in water. They are biodegradable and last as long as a couple of years. They can be mixed into soil before planting and cut watering frequency in half. Follow the directions on the label and do not overapply. Some potting-soil brands already include water gel polymers. Experiment and see if you notice a difference, especially in window boxes.

Self-watering pots have a reservoir at the bottom that is filled through a tube. The water wicks up through the soil to keep it adequately wet. These pots are expensive, so you might want to experiment before committing.

Fertilizer

Be sure to use bloom-booster fertilizers. These have higher concentrations of phosphorus that encourage flowers. Nitrogen promotes foliar growth. Osmocote is a popular slow-release fertilizer that supplies nutrients through the growing season. Many potting soils come with it already mixed in, although you can buy the soil and fertilizer separately and mix it yourself.

Soluble fertilizers are mixed with water and applied every two weeks for quick results. To keep fertilizer salts from building up, water until it comes out the drain holes and be sure to empty the saucer when done.

When my daughter was young, she was afraid to shower because a vampire might come out of the drain and get her. Oh, sweetheart, vampires don't live in the shower. They live under your bed.

I didn't say that, I swear. I was thinking it, but I didn't say it.

Tony Bertauski is a horticulture instructor at Trident Technical College. To give feedback or request specific column topics, e-mail Tony at tony.bertauski@tridenttech.edu.