Joe’s Journal, Fall Edition: A Reversion to Sports
In one of our last blog, we highlighted fasciation, a unique – and often strange – plant growth. In this issue, we’ll turn to plant sports!
Ever wonder where the wide array of dwarf plants comes from? Well, they originate naturally and randomly on plants with a normal (type) pattern of growth.
Botanically, a “sport” is a part of a plant with a change in morphology, or form. Sports may differ by foliage shape, foliage color, flowers, fruit, or branch structure. Some common examples of sports are the nectarine, which developed as a bud sport from peaches, and the ‘Pink Lemonade’ lemon, which is a sport of the “Eureka” lemon.
Sports are often propagated vegetatively to form new cultivars that retain the characteristics of the changed form. Here are some common examples found in the landscape garden.
The Hinoki Cypress
The Hinoki cypress (Chamaecyparis obtusa) is a species of cypress native to central Japan in East Asia, and widely cultivated in the northern temperate climates for timber and as an ornamental. The nursery trade offers a wide range of cultivars. The range of cultivars include dwarf forms, and forms with yellow leaves. One dwarf form is ‘nana gracilis,’ shown below.
The “type” (or standard variation) plant has foliage that is soft and feather-like, and can grow up to 115 feet tall. By contrast, ‘nana gracilis’ may only attain to 36 feet in height. A bud sport from the type tree formed a branch with compact growth, which was then propagated (rooted) to form a new dwarf plant. Sometimes in the landscape a reversion can occur, that is, growth reverts back to type.
Close-up of reverted growth
Examples of other conifers that originated from sports include weeping eastern white pine, golden thread-leaf cypress, and birds nest spruce.
Weeping Eastern White Pine
Weeping eastern white pine is a needled evergreen in the pine family (Pinaceae) and is native to North America. This variety (Pinus strobus ‘Pendula’) has long, twisting, pendulous branches and an irregular form. The branches spread horizontally, then droop. Its mature form depends on the training and pruning when young. It ought to be trained when young to develop a central leader, otherwise it may become more of a sprawling shrub than a tree. It can attain a height of 16 feet, and a width to 20 feet.
Golden Thread-Leaf Cypress
Golden thread-leaf Sawara false-cypress (Chamaecyparis pisifera ‘Filifera Aurea’) is a semi-dwarf, evergreen shrub in the cypress family (Cupressaceae) that is broadly cone-shaped and slow growing. The foliage is thread-like and golden yellow on weeping branches. The species is native to Japan, and this cultivar originated as a sport with golden needles found on C. pisifera ‘Filifera,’ a cultivar with thread-like, drooping shoots. The scientific name derives from the Greek words for dwarf and cypress, and the Latin word for “pea-bearing,” referring to the small, rounded cones the plant produces.
Birds’ Nest Spruce
Picea abies ‘Nidiformis’ is a dwarf, needled evergreen shrub in the Pinaceae (pine) family. Named “birds’ nest spruce” due to the depression (nest) in the middle of its compact, mounded habit, this cultivar of the Norway spruce has been known to the nursery trade since the early 1900s.
Birds’ nest spruce is grown for its beautiful light green or gray green foliage. The branches are spreading and grow horizontal or at a slight upward angle, making its form a dense, broad, shrubby, flattened globe. Although it typically grows to 1 to 2 feet tall and 3 to 4 feet wide, it can mature to up to 8 feet tall and 10 to 12 feet wide in 30 years.
This is just a sample of plants derived from sports. Once you see one, you will begin to notice them where they occur, a type of “gardening sport”!
~ Signing off for now, Joe
