Unlike many arborvitaes, "Emerald Green" arborvitae (Thuja occidentalis "Emerald Green" aka "Smaragd") maintains a compact size, growing only 15 feet high by 3 to 4 feet wide. Planted in a pot, it remains even smaller and makes a striking evergreen container plant at an entryway or on a patio. Like most plants, an "Emerald Green" arborvitae needs special care when planted in a pot.
Select a large, ceramic pot that holds at least 20 gallons of potting soil. "Emerald Green" arborvitaes live 20 years or longer, so be sure to get a durable pot large enough to accommodate a full-size shrub.
Plant the arborvitae in a high-quality potting soil that contains perlite or vermiculite to retain moisture and improve drainage. Place the pot in full sun or partial shade.
Water the shrub frequently to keep the soil evenly moist. Arborvitaes are fairly drought-tolerant when planted in the ground, but they dry out quickly in pots and might not survive.
Prune the arborvitae back occasionally to maintain its size and shape. Prune off just the tips of the branches, but don't prune back to old wood. The plant won't put out new growth on old wood and may eventually die.
Fertilize the shrub every three to four weeks during the growing season with an all-purpose, water-soluble fertilizer. "Emerald Green" arborvitaes don't usually need much fertilizer, but a container-grown plant requires more nutrients than one grown inground.
Wrap the shrub in burlap or move it to the garage during cold weather unless you live in a warm climate. "Emerald Green" arborvitaes are hardy between U.S. Department of Agriculture plant hardiness zones 4 through 8, but containers don't provide as much insulation as the ground does. Plan on providing some winter protection if you live below zone 8.
Things You Will Need
- Ceramic pot
- Potting soil with vermiculite or perlite
- Pruning shears
- Water-soluble plant food
- Some arborvitaes, such as "Pyramidalis," grow 20 to 30 feet high. Make sure you're getting "Emerald Green" arborvitae to ensure a small, compact form.
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