Container Trees

Caring for your Container Tree

Container Size

To determine container size consider current plant size, eventual plant size, and your space available. The pot should be at least 6” larger in circumference than the current root ball. The plant may need to be up potted or root pruned in future years to maintain a healthy specimen. If the pot is much larger than the current root ball, watering challenges arise.

Watering

All container plants require more water than the same plant in the ground. In hot summer months the container may need watered every day, depending on the size of the pot. If a small plant is placed in a very large container it can be difficult to keep the actual root ball moist. Take extra care to soak the root zone and not just the excess potting soil.

Soil and Fertilizer

We recommend potting soil for container plants because it offers the best drainage. Never use dirt dug from the garden. Fertilize once a year, in the spring, with an all-purpose fertilizer of your choice.

Planting in the Ground

When ready to move your plant from a pot into the ground dig a hole twice as wide and the same depth as the current pot. Fill the hole with water and allow to drain if the soil is dry. Gently loosen the roots if necessary and lower the tree into the hole. Mix in a handful of bone meal or rock phosphate to encourage root development, or add some starter fertilizer if desired.

Current research recommends not adding compost to the soil. Simply backfill with existing soil around the root ball. Water thoroughly to settle, even on a rainy day.

Soil and Fertilizer

We recommend potting soil for container plants because it offers the best drainage. Never use top soil or soil dug from the ground. You can mix in up to 20% compost in your containers at planting time, or use it as a top dressing for added nutrients.

It is important to note soil in containers should ideally be refreshed every 3-6 months, but at least every 1-2 years if using fertilizer.

Liquid fertilizers are fast acting and convenient, as you apply them when watering. Slow-release fertilizers are simple to apply infrequently. If you have any questions stop by our Information Desk. We’re happy to help!

Design Tips

• Choose a few foundation plants, like small to moderate trees and shrubs to give your garden structure and year-round interest. Statuary and pottery also work.

• Decide the purpose of your garden (curb appeal, improved view, outdoor dining area, etc.) to create a layout. The benefit of having your plants in containers is that you can move them! Keep in mind that containers, once planted and watered, can be quite heavy. Consider getting casters or pot lifters for safety.

• Draw out a rough sketch of what you want your garden to look like and where things will go. Use Pinterest, design books, magazines, or blogs to find what styles inspire you.

• Evergreens will keep your garden looking good and alive year-round. Without them, winter will bring empty-looking pots, bare branches, and unattractive, dead material.

Container Trees

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Favorite Container Trees

Trees under 10’ for patios, containers, and small places.

Please note that these suggestions are subject to seasonal availability.

Acer palmatum - Japanese Maple. There are many varieties which stay under 10’. These maples prefer morning sun and afternoon shade. Some varieties can take full shade. All are deciduous. Zone 5.

Betula pendula ‘Trost's Dwarf’. Thread- like, bright green leaves that turn to yellow in the fall. Slow growing to 3-4’ tall/wide. Zone 2. Needs excellent drainage.

Betula nigra ‘Fox Valley’. Creamy tan, peeling bark with yellow foliage in fall. Reaches 10-12’. Very rare size for a birch. Full sun.

Ceanothus spp. - Wild Lilac. Many varieties available, size dependent upon species. Most are easily pruned into tree form. Zones 6-7.

Chamaecyparis obtusa varieties - Hinoki Cypress. There are dwarf varieties which do not grow more than 6”/year. These slow growing varieties do not surpass the 5’ mark. They are evergreen and come in many colors and textures. Zones 4-8.

Chamaecyparis thyoides ‘Red Star’. A unique white cedar with gray-green, star- shaped foliage that turns maroon in winter. Grows 3-6”/year in an upright, conical form. Hardy to Zone 3.

Cornus alba or stolonifera cultivars - Red twig dogwoods. These shrubs can be easily trained up into a tree form. They can reach 8- 10’ tall & wide. Beautiful, brightly colored twigs in winter. Sun or part shade. Zones 2-8.

Cryptomeria japonica ‘Black Dragon’. A slow growing conifer reaching 8-10’ tall. Black -green foliage on upright stems. Evergreen. Full sun. Protect in winter. Zones 5-6.

Lagerstroemia indica ‘Petite Pinkie’ - Crape Myrtle. An ideal choice for a hot spot. This shrub/tree is attractive all year. It reaches 5’ tall and 4’ wide. Clusters of bright pink flowers in late summer are followed by blazing fall color. Deciduous. Zone 6-8.

Larix decidua ‘Pendula’ - Weeping European Larch. Gorgeous deciduous conifer with lime green needles in spring, which turn golden in fall. Stake to desired height. Zones 2-6.

Malus ‘Coralburst’- Crabapple. This variety reaches only 8-10’ tall and forms a dense head. Bright coral buds open to double pink flowers. Small bronzy-orange fruit. Deciduous. Full sun. Zone 5.

Picea glauca ‘Conica’ - Dwarf Alberta Spruce. Classic cone-shaped conifer. Grows 3-6”/year. Matures at 8-12’ tall and wide. Easy to prune to desired size.

Rhus typhina ‘Tiger Eyes’ A newer variety of cutleaf Sumac. Bright foliage turns vibrant red in fall. Eventually reaching 6’ with a broad canopy. Sun to part shade.

Ribes sanguineum ‘King Edward VIII’ - Flowering currant. Beautiful teardrop, pink flowers in spring. Vibrant fall color before the leaves fall to reveal peeling bark. Reaches 8’ tall and 3-5’ wide. Part shade to full sun (with ample water). Zone 5.

Salix caprea ‘Pendula’- Weeping Pussy Willow. This pendulous form reaches 8’ tall and wide from the graft. Silvery gray, furry flowers in February/March. Requires a lot of water if kept in a container. Zones 4-8.