Q: My pool deck is lifting in several places as a result of the invasion of roots from my neighbor’s tree. The tree is 50 to 60 feet tall with a canopy at least 70 feet wide. It is deciduous with all leaves at the end of long slender branches. I have dug a few trenches to discover 4- to 6-inch roots coming from under our block wall into our yard and moving toward both the pool and our house. I know that I need to stop these roots but I am not sure what is the most effective means. Are there effective solid or chemical barriers? Will the severed roots decay and allow the pool deck to return to something approaching normal?
— Chuck Zanghi,
Thousand Oaks
A: Even after cutting through the roots at your property line, you will still have to redo those parts of your deck that have been raised. It will take many, many years for the roots pushing up your deck to decompose. Root barriers made of modular, hard plastic panels are effective at stopping roots from traveling across property lines. Root barrier panels are snapped together to create a barrier as long and as deep as you desire. I would line a trench at least three feet deep with the root barrier panels to ensure that roots from your neighbor’s tree do not cause further problems.
In the world of plant breeders, small is both beautiful and profitable. Over the last 20 years or so, many popular shrubs and perennials have been shrunk or compacted through hybridization or bio-engineering. This down-sizing trend has paralleled the increased popularity of town homes and condominiums with their small, patio gardens. The trend towards gardening in containers has also increased the popularity of smaller plants.
Consider lily-of-the-Nile (Agapanthus), a garden favorite that begins blooming about this time of year. In addition to the regular species with stems up to 5 feet tall, you have its half-size equivalent, `Queen Anne’ and its miniature version, `Peter Pan.’ If you have a passion for mock orange (Pittosporum Tobira) shrubs, then you should be aware of the compact `Wheeler Dwarf’ and `Turner’s Variegated Dwarf’ varieties. It is of interest to note that among oleanders (Nerium oleander) the only varieties that have shown resistance to the oleander leaf scorch disease are the semi-dwarf `Petite Pink’ and `Petite Salmon’ varieties.
In the fruit tree department, apples, oranges and lemons can now be plucked from trees that do not grow more than 5 to 10 feet tall, depending on the variety.
The multicolored, evergreen foliage of heavenly bamboo (Nandina domestica) can now be found on many semi-dwarf and dwarf configurations of that species. One of my favorites is `Gulf Stream,’ which grows to a little more than 3 feet tall and provides a continuously lush and unflappably fresh presence in the garden. The 2-foot-tall `Filamentosa’ has a much different look than the rest of its Nandina kin with narrow, almost thread-like leaves.
Other familiar plants with dwarf cultivars include escallonia (Escallonia `Newport Dwarf’), myrtle (Myrtus communis `Compacta’), sweet pea shrub (Polygala fruticosa `Petite Butterfly’), Texas ranger (Leucophyllum frutescens `Compacta’), and Peruvian lily (Alstroemeria `Peruvian Princess’).
At the nursery the other day, I saw dwarf cultivars of Gaura Lindheimeri. Gaura (rhymes with Laura) is one of the toughest long-flowering perennials you can find, a member of that elite class of so-called bullet proof plants. Gaura can grow in either dry heat or humidity in almost any kind of soil. It easily reseeds and will spread in rapid fashion. Possessed of a strong tap root, you can cut it to the ground when it wears out, only to see it return to life with renewed vigor.
The one knock against Gaura was its diffuse and floppy growth habit, which made it a nuisance to plant near walkways or entries.