Puttering with Pots!

You can garden in small spaces, or create spots of color in otherwise boring landscapes.

Perhaps you are a hobbyist or collector--I like the term "plant enthusiast. Pots enable you to provide for the special needs of certain plants.

You bought something on a whim? Something with special needs? Been there, done that. Many of our favorite plants need special fertilizers, winter protection. Containers give us more flexibility about soil and location.

It can reduce garden-related stress: putting together a color bowl can be a quick, easy project providing an immediate sense of completion in our busy lives!

A landscape project seems overwhelming to your child, but putting together a container garden is a simple activity that you can do together. It's perfectly in scale with their size and aspirations.

Gardening in containers gives immediate results, and can be an easy way to get color or greenery during very hot or cold, dreary days.

Learning how to make plants live and thrive in pots simply increases your satisfaction. So here are some basics.

Which type of container is "best?"

Plastic is lightweight, portable, and cheap. It doesn't "breathe", so plastic pots tend to need less frequent watering. Downside: they dont provide enough weight to anchor a top-heavy plant.

Clay is durable, but breakable. It does breathe, and it tends to accumulate salts in areas with hard water. Clay pots vary from lower-quality Mexican pots, which last a couple of years, to harder-fired Italian pots, all the way up to dense glazed ceramic pots.

Wood ages gracefully and is long-lasting. Well-made redwood planters can last for decades. Oak barrels are very economical, and last for several years if they are never allowed to dry out.

What potting soil should you use?

Quality varies, and you do get what you pay for. Inexpensive blends often contain shavings or other materials that aren not fully composted. As these break down, harmless fungus will grow on them—and fungus gnats will happily dwell on the fungus. These are the little black flies that flutter aimlessly around your plants. Not harmful to the plant, but annoying and often a sign that you may be overwatering.

A good quality potting soil is a blend of compost, sand, and peat moss, and may have other additives such as fertilizer (organic or chemical), and pumice, bark, or perlite for drainage. It should drain quickly but retain moisture.

Most additives do not encourage diseases, so potting soils don't need to be sterilized. Using compost or soil from your own garden is not recommended, as these can be sources of weeds or pests. You can sterilize garden dirt in the oven, but it smells really, really bad (I'm speaking from experience here).

Special soils for certain plants most of the special blends simply vary the basic ingredients to increase drainage, or adjust the pH. Cactus, bonsai, African violets, ferns, orchids are all examples of plants which need faster draining soil. Plants that get big and heavy can tip over if the mix is too light, so cactus, succulents, and trees may be grown in a mix that has more sand to increase the weight.

What do container plants need?

There are four things all plants need to grow--air, light, water, and nutrients. What made Aunt Nellie seem like a successful gardener was that she knew how her individual plants varied about these needs. Container plants are more vulnerable and more sensitive because they are confined. But it is how we provide these basics that lead to success.

We can't do much about air! Ok, keep your pots out of strong winds, as container soils dry out quickly. The other three--light, water, and nutrients--are within our control.

Remember: a plant in the ground has a reservoir of water and nutrients nearby that the roots can seek and draw from.in a container YOU are providing ALL of the water and food!

Light: How much sun or shade are you gardening in? Container plants are easier in at least partial shade. Some plants will take full sun: Citrus, cactus and many succulents, kitchen herbs. Indoor light is much trickier. Most houses have about ¼ - 1/10 the light of outside. Very few flowering plants will thrive in that. Many popular house plants such as Philodendrons and African Violets are from the dark understory of tropical forests. Plants that are not getting enough light stretch, have paler leaves, and are more prone to rot.

Direct sun on a dark container cooks roots! The temperature of the soil on the west side of a nursery pot is lethal. Shade the pots, paint them, set them inside larger pots – do whatever it takes to keep direct sun off the container.

Watering is Job One with container plants in the Sacramento Valley! The more rootbound a plant, the more often it needs water. The bigger the pot, the longer you can go between waterings. An oak barrel typically needs water only once or twice a week. Anything smaller may need water daily during extremely hot weather; more typical is every 2 – 3 days. Grouping container plants together can help shade the pots and make watering easier.

Water-retaining polymers came on the market several years ago. These absorb water (100x their weight!) and then release it slowly as the plant needs it. But hard water significantly reduces the effectiveness of polymers. Peat moss is nature is version, absorbing 10 – 15x its weight in water. But when it dries out, peat moss is very hard to re-wet. So it should not be more than about 1/3 of the total mix.

Food: Most potting soils contain enough fertilizer to last 2 – 3 months. Additional organic fertilizers can be mixed in the soil at the time of planting. Slow-release resin-coated types (Osmocote is the best-known) can be put on the soil surface once a season, releasing a trickle of fertilizer with each watering. The popular soluble fertilizers (mix and spray!) are great for flowers.

Repotting is done every year if you want the plant to grow bigger, or if you find it is so rootbound that you are having to water daily. The new pot should be 2 – 4 in diameter larger. Transplanting is best done during mild weather. But as long as you provide food and water, a plant can live, very rootbound, in the same pot for many years.

Note: most indoor plants are rootbound when you buy them. They are often in a potting mix that is designed for the growers needs—lightweight for shipping, or for greenhouse watering systems. If they are flowering, repot them as soon as they finish. Foliage plants should usually be repotted right away.

What are you growing, and how long do you want it to stay in that container?

Specimens: cycads, palms, dracaenas, cactus and succulents are examples of plants that can stay in the same pot for longer than a human generation! People who collect these plants use tricks to keep them healthy and easy to care for. They usually use a somewhat denser soil mix to accommodate the weight of the plant (this also helps retain water and food), and find clay or ceramic pots more effective. It's worth buying a fancy pot to show off a specimen plant.

Bonsai is a specialized container gardening skill. Roots are pruned each year to remove ¼ - 1/3 of the total mass, then the plant is repotted in the same (or smaller!) pot to intentionally stunt it and develop a wizened look. Trees may be kept this way for hundreds of years. Most bonsai are best outdoors, and are easiest to grow in partial shade. Bonsai may need water daily in hot weather here.

Seasonal: at the other end of the spectrum are color bowls, which are basically flower arrangements with roots. Check out Sunset Magazine and you'll see these artistic groupings. Note the creative use of foliage plants, grasses, and succulents—these are tricks to keeping the arrangement looking acceptable longer than you will get from annual flowers alone.

Even seasonal annual flowers are much more satisfactory in larger containers. A barrel or large pot allows the plant to root deeply and reach its full potential.

By the way: get ruthless with annuals! When they look ratty, pull them and pop in some new ones! What made Aunt Nellie a successful gardener was that she knew when a plant was done and threw it in the compost pile!

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