The Challenge with Container Gardening, or the Mystery of the Disappearing Hedge

Strange title perhaps, but I promise to explain.

The blaze of colour and foliar-festivity below is, unfortunately, a classic case of a mature over-planted garden. For a long time, the yew hedge has framed a copse of magnificient magnolias and an understorey of weeping Japanese maples, rhododendrons, and azaleas.

In recent years, the cup has begun to spilleth over.


In particular, the back corner of the yew hedge has lost vigour, and one after another, the individual plants are yellowing out and creating unsightly gaps. What to do?

The owner, being attached to his hedge (figuratively speaking), wanted to try replanting new yews in the gaps. Seemingly at random, the new yews also yellowed and failed to thrive.

After two years, this "new yew" was dug up. Notice the root-ball, below... (Also notice how close the magnolia trunks are to the hedge, above)...

No new roots. Ach!

The other significant observation was that the new yew's root ball was swarmed with magnolia roots--over and around and under. You can distinguish magnolia roots from surrounding plants' roots because magnolia roots are as fragrant as fine (but dirty) perfume.

So we have to see the forest for the trees--a classic example of an old expression.

This planting can be considered a container-planting--just on a much grander scale than your average balcony-pot. The plants are indeed contained on all sides by the street and driveway. Even though the bottom of the "container" may be open to the ground, plants have defined root structures: in this instance, yews and magnolias and rhododendrons and azaleas have shallow roots.

In short, the magnolias are winning.

In this case, the magnolias are winning both below and above ground, because, given the choice, the owners prefer magnolias over yews. The solution, sadly, is removing some plants from the "container." A hardscaping solution (fence) will have to be found for the privacy issues on that corner--and perhaps the length of the roadside in the future.

This reflects the particular challenge with container-planting in general. Restricted root-space increases competition and stress on plants, so initially underplanting a container will ensure longer-term health. Another approach is to plant your preferred specimen in a pot, and temporarily embellish the pot with annuals or plants that you plan to remove. As the preferred specimen matures, it roots can then claim the available space.