When I first moved to my current garden, I gardened strictly in containers for the first two years. I covered my 800 square foot deck with everything imaginable, leaving barely enough space for eating and sitting. During that time, I learned a lot about container gardening from both failures and successes. The three most important lessons I learned are: anything can grow in a container; the potting soil matters a great deal; and containers must be cared for and freshened up throughout the year.
Anything Can Grow In A ContainerAnything that grows in the ground can grow in a pot. Containers are not just about annuals. More can be added to the garden by varying the contents of your containers. For example, two years ago I planted a culinary herb garden near our Children's Garden. I found that it was too far from the house to duck out while cooking for a quick snip at an herb or two. So, last year I relocated the herb garden into pots on the deck. I have one huge pot with dill, chives, and basil; one with rosemary, tarragon, and various kinds of thyme; and a few smaller ones with different varieties of basil. I usually grow any new roses I want to try in pots: everything from the small Clotidle Soupert to the rampant climber Cecile Brunner. Evergreens, shrubs, grasses, vines, even trees can be grown in pot. I have had a lilac growing for five years now in a pot on the deck and each year the blooms get better and better.
When growing shrubs and trees in pots for the long term, I've learned to treat them as really large bonsai plants. Each year, I renew their soil by removing some and adding organic amendments and manure. Also, every few years I trim off the outer most roots of the plants on one side to allow more root development without the danger of the plant becoming root bound. With this treatment, my lilac is still growing in its original planting pot.
The Potting Soil Matters a Great DealAs regards the potting medium, consider again what will be growing in the pot. For tropical plants that like a lot of moisture like elephant ears, I use a heavy potting soil with lots of organic matter added to it that will hold moisture well. This year I am mixing the organic Gardeners' Gold potting soil with dehydrated cow manure. For my roses, that mixture would kill them because the water would sit too long close to their roots. So for roses, I could take the same Gardeners' Gold, but to it add perlite and cow manure so that the proportions are 1:1:1. This yields a rich, well draining soil. For a plant which likes leaner soil, take out the cow manure and use a less organic potting soil as a base.
Containers Need Year-Round CareOnce the container is planted, the care for that container does not stop there. Since containers are their one ecosystem, I must be very attentive to watering, particularly during heat waves, and fertilizing. Usually, I water every morning and sometimes again later if the weather has been particularly brutal. I also fertilize once a week with fish emulsion, sea weed emulsion, or a liquid complete fertilizer.
In the border, I often use containers which I can change with each season. The pot that sets in the front of our library began in the spring with a melange of daffodils, tulips, and muscari ringed with pansies. In June, I replaced the planting with red hot pokers, caladium, and a very tall phormium. Then in autumn, everything except the red hot poker came out. I add then a three foot tall yellow twig dogwood, pansies, and a few medium sized gourds.
After Thanksgiving, I removed the gourds and replaced them with white pine boughs and trimmed back the leaves of the red hot poker for neatness. For this spring, I left the dogwood and the red hot poker. I have added pink primroses and pansies. The constant changing of the containers offers something new for each season and gives me more opportunity to experiment.
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Before the frost, I also move my non-hardy containers that I want to over-winter either into the garage (roses, fig tree) or into the house (elephant ears).
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Containers add so much to my garden and plant knowledge. It is a great way to experiment with different plants and combinations without the commitment of planting in the ground. Also, seeing how a plant thrives in a pot with a specific planting medium helps me understand under what conditions it will thrive in the ground.
Since my prior post about pruning a pee gee hydrangea, I have received numerous follow-up questions on why and how to prune other types of hydrangea. Most of the hydrangea in the garden are either mopheads or lace caps (pictured). These belong to the group Hydrangea macrophylla. Most macrophylla bloom on wood or stems more than a year old. 
In late spring these can be pruned to remove dead wood. Since it is very difficult for me to distinguish between the dead and living wood in dormant hydrangeas, I wait until late April when the stems have begun to leaf out. Then I cut the dead wood at the base of the plant as far down as I can reach. This will allow plenty of new room for new shoots to emerge.
If your hydrangea macrophylla (pictured on Goldberry Hill) is getting too big and you want to reduce its size, prune it in mid summer after it has bloomed. You can either cut back the stems or just take out some of the longest wood at the base of the shrub. By waiting until July, you will have blooms and give the shrub time to prepare new growth to flower the following year. You do not have to do this type of pruning unless you need the space. Naturally hydrangeas develop a nice rounded shape. 
by John Scarman published in 1996. He has vast experience with old roses through his work at Rosemany Verey's Barnsley House (
