We’ve been growing these for 20 years and they are still our favorite variety of tree collard. When most people talk about tree collards, this is often the one they refer to. Purple Tree Collards produce all year long and taste especially good in colder weather. They turn darker purple tones in Winter and are lighter blue-green in warm months. Purple Tree Collards rarely go to flower and seed. Purple Tree Collards can be grown multi-trunked and kept as low as 3 feet tall or as tall as 12 feet. If grown with a single trunk, it will need a strong support and will be quite woody and bare down low. For this reason, we prefer to tip prune Purple Tree Collard plants to keep them bushy and productive. 

This plant is from a chance cross at a local community college. They are a vigorous tree collard with large leaves measuring over 2 ft’ and weighing over 1/2 pound. Merritt Tree Collards have a round dense shape when young and eventually grow up to 7 feet tall after 5 years. They do often go to seed in spring but they are still productive in the flowering/seed pod phase. Merritt Tree Collards can be propagated from thinner cuttings or very thick stalks by cutting them with a saw and placing them in a large pot with high quality potting soil. You can also save seed and come up with interesting hybrids if  you have other brassicas blooming at the same time. These seedlings tend to have sturdy, thick stalks, and to be more climate adapted than the mother plant. They grow well in USDA zones 11-8, and marginally in zones 7a and 7b. Some of the seedlings have been reported to survive New England winters without protection.

Taunton Deane is a perennial kale from England, that appears similar to the Purple Tree Collard at first glance. The leaves are around 8 inches long and are silvery green in color with purple midribs. In Winter, the plant will increase purple coloration in low temperatures but this is a seasonal shift. It is also known as ‘Cottager’s Kale’ a name which occurs frequently in gardening journals from at least 1859 onwards although it is unclear as to whether the Cottage’s Kale referred to was genetically identical to this one or not. Charles Darwin even was known to have grown this plant, so it has enjoyed a rich and long history in the UK. There were apparently more perennial kales in the past, and this is one of the few that has remained.

The flavor profile of Taunton Deane Kale is refreshingly different than their tree collard cousins. They remain sweet even in late spring months. Like the Purple Tree Collard, it is shy to flower and produce seed, but it does on occassion. In Europe, it is grown in food forests and homesteads much like the Purple Tree Collard. Until recently it hasn’t been readily available in the United States, making it a rare perennial kale.

In England, plants can grow 6 ft tall (or more) and are more tolerant of heavy rain and cold than most tree collards. Our plants are grown in part shade and have endured 3-4 feet of snow for a few weeks. After the snow melted and temperatures warmed, you couldn’t possibly imagine that they had just been under the weight of deep snow. They also withstand hot, dry, summers up to 112 degrees in part shade. Plant 3-4 feet apart. Perennial in USDA zones 7-10.

Dinosaur Tree Kale/Collards
These are from a seedling grown by Rebecca Newburn, whose Purple Tree Collards flowered at the same time as her Lacinato (dino) kale and she saved the seeds and grew them out. At the time, this was her favorite of the seedlings. It looks somewhat like a lacinato kale plant, but grows more or less like a small tree collard. The main drawback is that it flowers vigorously each spring, which slows down leaf production. You can eat these flower shoots like small broccoli. Once they have flowered and set some seed you can cut back the flower stalks and the plants will resume leaf production.They have a milder taste than Purple Tree Collards.  Dinosaur Tree Collards are a smaller, less vigorous tree collard that is naturally multi-trunked and grows to 3-5 feet maximum.

This in an edible and ornamental perennial kale that grows to a nice compact 2-3’ bush and doesn’t get leggy and woody like tree collards can.  With its striking variegated leaves, many people wouldn’t realize that this is an edible plant. It is less productive than tree collards due to its smaller size and smaller leaves, but this is a good option if you are looking for a great ornamental edible. This plant rarely blooms. Daubenton kales are much more difficult and slow to propagate than tree collards in our experience. NOT CURRENTLY AVAILABLE.

Big Blue Tree Collards are a 2020 introduction and extremely limited perennial tree collard. It is a naturally occurring garden hybrid from the Berkeley Farm that appears to be a cross between the Merritt Tree Collard, Dino Tree Collard, and maybe even Purple Tree Collard. Big Blue gets between 3 and 4 feet in height, and appears to naturally branch into a mid-sized shrub form. Within the first year or two, wide stalks 1-2 inches in diameter can form. Once the tree collard reaches 2-3 feet in height, it would be best tied to a sturdy stake as it can be top heavy in storms and high winds. Leaves can get up to 1 1/2 feet long and are a stunning blue-green color with a hint of pink/purple in the stems. They are crinkly like Dinosaur Tree Collards, but much wider and less linear.

Because it is a new introduction, at this time it’s cold hardiness or heat tolerance is unknown. Based on past experience, it should be at least as cold and heat tolerant as its parentage. One can expect it to be good in zones 8-11, and probably marginal in zones 7 A and B. It has performed well in several feet of snow and temperatures down to 28 degrees.

Ken Asmus of Oikos Tree Crops shared clones of his Michigan Tree Collard with Project Tree Collard. This hardy tree collard came from a plant that has been outside for the last 5 years in USDA zone 5-6, and has survived temperatures to 0 F. Michigan Tree Collard is a vigorous, silvery colored tree collard that has purple hues on the stems and new growth. Flavor is similar to other tree collard plants. It may be tolerant of even colder winter temperatures than zero, and even if it appears to have died above ground, it re sprouts from below the soil line once the growing season resumes. Some have hardy enough stems to stay green and sprout slightly above the ground. It grows up to 6 feet tall, and if given fertile, well-drained soil with regular water can reach 3-4 feet high in one year.