The Science Behind the Art™

Articles

Tag: Potted

Growing Container Blueberries

Compact berries for containers are popular, and more and more varieties are being developed for container culture. Compact blueberries are particularly good for growing in pots, with good care. The northern native berries have specific growing needs. Follow the guidelines here, and you will have bountiful berry pots in no time. The best blueberries for containers are shorter species, such as lowbush blueberries (Vaccinium angustifolium) rabbiteye blueberries (Vaccinium ashei), and new compact designer blueberries (Vaccinium hybrids).

Growing Blueberries in Containers

With good care, blueberries will produce berries each year. Plant more than one pot of berries for cross-pollination and best fruiting.

Compact blueberries of all types grow beautifully in spacious pots. With good care, the long-lived shrubs can survive for years, so choose strong, thick, weatherproof ceramic pots big enough for them to grow to maturity–18″ pots or larger depending on the final size of the plant. (click here to read more about the best weatherproof pots)

Blueberries naturally grow best in more acidic soils (pH 4.5-5.5) with good drainage, often sandy soils, so we recommend a peat-based mix amended with some sand and perlite. Of our product line, we recommend Fafard Natural & Organic Potting Mix, which is OMRI Listed for organic gardening and also provides good aeration and porosity. Because blueberries are acid-loving, I like the look of mulching the soil surface with fine, dry white pine needles. They hold moisture, keep weeds down, and look good.

Place your blueberry pots in a location with full to partial sunlight for the best fruiting and growth–more sun is tolerated in areas with milder summers. Blueberries will tolerate shade, but they will not set as much fruit in a shadier site. During the high heat of summer, protect them from the scorching midday sun.

Water blueberries regularly. The soil should be allowed to become slightly dry between watering. Feed blueberries as directed using a fertilizer formulated for acid-loving plants. Repotting is necessary every few years and the shrubs should be pruned if they develop dead growth or crossing, ungainly branches.

Pruning Blueberries

Even compact blueberries need occasional pruning. Here are four guidelines to follow when pruning blueberries.

  1. Prune just after berry harvest.
  2. Maintain one strong fruiting cane (branch) for each year of growth, starting in the shrub’s fourth year.
  3. Older canes can be replaced by stronger, newer fruiting canes after the shrubs have reached 8-10 years.
  4. Remove smaller, weaker, lateral branches to encourage stronger fruiting branches.

The Best Blueberries for Containers

Peach Sorbet® blueberry has a beautiful habit, good fall color, and tasty berries. (Image thanks to Bushel and Berry)

The best blueberries for containers are shorter species, such as lowbush blueberries (Vaccinium angustifolium, USDA Hardiness Zones 2-8) rabbiteye blueberries (Vaccinium ashei, Zones 7-10), and new compact designer blueberries (Vaccinium hybrids).

Two choice rabbiteye Blueberries are ‘Tifblue’, which has large berries midseason, and ‘Brightwell’, which produces large clusters early to midseason. Bushel and Berry® arguably sell the finest designer Blueberries on the market. Their boxwood-like Blueberry Glaze® and cute, round Jellybean® (Zones 4-8) have delicious fruit, tidy habits, and bright fall color. Finally, Pink Icing® (Zones 5-10) produces loads of tasty fruits on shrubs with pink new growth.

The largest blueberry in the group is the hybrid lowbush blueberry, Northsky®, which forms a tiny round shrub reaching 2-3 feet. The 1-2 foot ‘Tophat‘ is a common favorite. The tidy round bushes product loads of berries once mature and producing.

I encourage blueberry growers to watch the following video to learn more about blueberry cultivation.

Potted Holiday Trees: Selection and Care

Potted Holiday Trees: Selection and Care Featured Image

Small or large potted holiday conifers are fragrant, fresh and provide living beauty in the home, but which should you choose for outdoor planting, and how do you care for them after the lights and glitter are shed? The right care will ensure their longterm health. Here’s how to give them what they need for success.

Know Your Trees

When picking a live tree, know what kind it is, and make sure that it will fit into your landscape and grow well where you live. Don’t be fooled by the initial size. Many potted trees sold as tiny specimens grow very large. Truly compact trees sold during the holidays, such as dwarf Alberta spruce (Picea glauca ‘Conica’, USDA Hardiness Zones 3-6) or lemon cypress (Cupressus macrocarpa ‘Wilma’, Zones 7-10), can be planted in large, outdoor containers for several years. But, those that mature to a large size must be planted in the ground. So, you must know your trees.

Miniature Christmas trees with ornaments
Beware! Many holiday trees sold as potted miniatures will grow very large.

Here are some of the top holiday trees sold in North America. Each grows best in certain areas of the country. All of the full-sized evergreens mentioned need lots of space, sunshine, and well-drained soil.

Firs

Potted fir trees
Be sure to have a planting spot in your landscape for larger potted trees.

Chrismas firs have soft, flat needles, a perfect conical shape, dense branching, and wonderful wintery aromas. They make good landscape specimens, where they are hardy, and all grow to become large, regal trees.

Balsam fir (Abies balsamea, Zones 3-7): The remarkably hardy balsam fir is a fragrant, soft-needled evergreen that grows best in colder climates with cooler, more moderate summers. It has a dense, conical habit and standard forms can reach a whopping 50 to 75 feet when fully mature, so don’t plant one in a small yard or close to the house.

Frasier fir (Abies fraseri, Zones 4-7): Comparable in growth, habit, and fragrance to balsam, Frasier fir is an Appalacian species from the southeastern United States that can take warmer summers, but because it grows in the cooler mountains it cannot take the intense heat of the Deep South. At full size, it reaches 30-50 feet.

White fir (Abies concolor, Zones 4-9): A fir for the Midwest and alpine West, white fir is more tolerant of areas with warmer summers. It has a conical habit with dense branching and soft, attractive, upright needles with a silvery cast. When mature, it can reach up to 60 feet.

Douglas fir (Pseudotsuga menziesii, Zones 4-8) is not a true fir, despite its name, but the pine is a good choice for those living from Pacific Northwest down to the Southwest. Soft-tipped needles cover its branches and when grown as a specimen tree it reaches 40-80 feet and has a broadly conical habit with more open branching than that of true firs.

Pines

Potted Christmas tree inside a home
Potted Christmas trees should be well watered while in the home.

White pine (Pinus strobus, Zones 3-8) is one of the most common native pines grown for Christmas trees. It is distinguished by its long, very soft needles, which some homeowners really favor. It makes a good landscape tree with open branching and can reach 50-80 feet.

Scots pine (Pinus sylvestris, Zones 3-7) is still sold but has fallen out of favor as a Christmas tree because of its painfully prickly needles. As a yard tree, it is equally undesirable because it’s prone to many pests and diseases. This is one to avoid.

Spruces

Dwarf Alberta spruce (Picea glauca ‘Conica’, Zones 3-8) is the most common potted holiday tree and is almost always sold as a pre-decorated, miniature for indoors or outdoors. After the holidays, it can be planted in pots for or in the garden. Eventually, dwarf Alberta spruce can reach 10 to 13 feet high but is very slow-growing, so it can be grown in pots for some time before planting in the ground.

Indoor Care and Transition

Christmas Tree
Indoor conifers should be kept inside no more than ten days.

All of these evergreens need cold winter weather to grow well, so bringing them into the warm indoors for too long can be detrimental to their health. Keep them in a cool garage or covered patio before bringing them inside. Once indoors, make sure that you place a basin below the pot for watering and keep the tree well-irrigated. Maintaining a cooler room temperature will reduce stress. Don’t keep them inside any longer than ten days, a week is better.

After the holidays, remove all decorations and take your tree outside. Very hardy varieties can remain in their pots if kept close to the home. Just don’t let the pots dry out. If the ground is warm enough to be worked, plant your tree straight away.

Planting

Getting ready to plant a potted evergreen
Getting ready to plant a potted evergreen.

All of these conifers like their soil to be slightly acid, rich in organic matter, and well-drained. Black Gold Canadian Sphagnum Peat Moss and Fafard® Premium Natural & Organic Compost are the best amendments to use at planting time. (Click here for the Morton Arboretum’s tree-planting instructions.)

Potted holiday trees are a long-term investment. While they decorate your home and bring joy to your family, care for them well. And, once planted, they will reward you with continued outdoor beauty for years to come.