Marionberry Is a 15-Foot Trailing Blackberry, Not a Bush: Two-Wire Trellis, a 13°F Cold Limit, and Why Oregon Has Over 90% of the Acreage

October 6, 2026

Updated on October 6, 2026

10 mins read

Marionberry is a trailing blackberry with 15-foot canes that need a two-wire trellis. Get the trellis spec, the 13°F cold limit and a Zone 6 winter plan.

The marionberry is a trailing blackberry, not a bush. Its canes can pass 15 feet and can’t hold themselves up, so it needs a two-wire trellis from the first summer. It’s also the least cold-hardy kind of blackberry: Oregon State University (OSU) says to expect damage to buds and canes below about 13°F, and that limit helps explain why more than 90% of the world’s Marion acreage is in Oregon. You can grow one in Zone 6, but only if you change how you handle the canes in winter.

This guide is a spoke of our full blackberry growing guide. It covers where the berry came from, the trellis spec, the two-year cane cycle, a Zone 6 winter plan, and a table for diagnosing what goes wrong.

What Is a Marionberry?

“Marionberry” is the market name for ‘Marion’, a named cultivar of trailing blackberry. OSU rates it very vigorous and thorny, with medium-size, soft, dark purple fruit and excellent flavor. USDA breeder George Waldo selected it in 1948 from a cross of ‘Chehalem’ and ‘Olallie’. It was released in 1956 and named for Marion County, Oregon, where it was tested.

Trait	‘Marion’ (per OSU)
Growth habit	Trailing; canes are not self-supporting and need a trellis
Cane length	More than 15 feet, and up to 20 feet in Oregon (OSU’s figures for trailing types)
Thorns	Yes
Hardiness label	Zones 6 to 9 (but see the Zone 6 section below)
Fruit	Medium size, soft, dark purple, excellent flavor
Crop	One crop a year, on second-year canes
Mature yield	10 to 13 pounds per plant (OSU’s figure for trailing types)

The pedigree matters because it explains the plant’s habits. About 44% of Marion’s genes come from Rubus ursinus, Oregon’s native trailing blackberry, which the Oregon Encyclopedia entry, written by OSU berry specialist Bernadine Strik, credits with outstanding flavor. Another 25% come from the Himalaya blackberry (R. armeniacus), a weed introduced from Europe, and 6% from red raspberry. The sources don’t say which parent supplied the vigor, but Marion’s “very vigorous” rating fits a plant with a weedy ancestor.

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It’s still a blackberry when you pick it. A blackberry keeps its white central core, the receptacle, attached to the fruit, so the berry is solid. A raspberry leaves that core on the plant and comes off hollow. OSU also notes that trailing blackberries tend to have a long shape, small seeds and an intense aroma, though its cultivar table calls Marion’s own shape “uneven.”

A whole elongated blackberry beside one cut in half lengthwise, showing the solid pale core inside the fruit — A picked blackberry keeps its white core (the receptacle), so the berry is solid; a raspberry leaves the core on the plant and comes off hollow

Why Does Oregon Grow Over 90% of Marionberries?

Oregon holds more than 90% of the world’s Marion acreage. According to the Oregon Encyclopedia’s 2024 update, growers there harvest 28 to 33 million pounds a year from about 4,500 acres, with farm sales over $11 million. Three things stack up behind that number.

The cold limit. OSU calls trailing blackberries the least cold-hardy of the three blackberry types. It expects bud and cane damage below about 13°F in December or early January, and damage at much warmer temperatures in the 20s during late fall and late winter. Most of Oregon’s Willamette Valley is USDA Zone 8, and even within Oregon, OSU says trailing cultivars can’t be grown in central, eastern or southeastern parts of the state without winter protection for the primocanes. Marion is no exception: the Oregon Encyclopedia says its production “may vary from year to year depending on the severity of the weather.”

The market. More than 95% of Marion goes to processing, as frozen fruit, puree and juice, and it’s usually machine-harvested in July. That fits OSU’s fruit description. A soft, flavorful berry is a good one for the freezer and a poor one for shipping. My reading, not a claim from the sources, is that this is why you rarely see fresh marionberries outside Oregon in summer.

The head start. Marion was bred and tested in the Willamette Valley, and the largest share of acreage is still in Marion County, “where the climate and soils of the Willamette Valley are ideal.” If you garden in Oregon, our Oregon planting guide covers the rest of the calendar.

What Trellis Does a Marionberry Need?

A simple two-wire trellis, built before the canes need it. OSU’s spec for trailing blackberries is short, and the table below puts each part next to the reason for it.

Part	OSU spec	Why it matters
End posts	Treated wood or metal, 3 to 4 inches across, 6 feet above ground	They carry the wire tension and the weight of the canes and crop
Line posts	Metal T-posts every 15 to 20 feet	Keep the wires from sagging between the ends
Top wire	High-tensile, generally 12-gauge, almost 6 feet high	Holds the fruiting canes up where the berries get air and sun
Second wire	4.5 feet above the ground	Gives each cane bundle a lower loop point
Optional third wire	3 feet above the ground	Spreads the primocanes out when you train them
Hardware	A wire tightener on each wire at one end, an anchor at each end	Lets you retighten as the wire stretches
Plant and row spacing	Plants 3 to 5 feet apart; rows 10 feet apart	Each plant gets room for a long primocane bundle

Diagram of a two-wire blackberry trellis showing end post height, top wire at almost 6 feet, second wire at 4.5 feet, optional third wire at 3 feet, and plant and row spacing — OSU’s trellis spec for trailing blackberries: two high-tensile wires, 6-foot end posts, plants 3 to 5 feet apart

The spacing leaves a puzzle. A plant on 4 feet of wire grows canes that run 15 feet or more, so they can’t run straight along the row. OSU’s answer is to split each plant’s primocanes into two bundles and loop each bundle between the top and bottom wires with one or two twists, one bundle each way. Training all of a plant’s canes in the same direction keeps them from tangling with the neighbor’s, which matters most with thorny Marion.

If you’re buying materials, look for 12-gauge high-tensile trellis wire, wire tighteners and metal T-posts (affiliate links). Heavier wire costs little more and spares you a mid-season rebuild.

How Does the Two-Year Cane Cycle Work?

Each cane lives two summers. It grows as a primocane in year one, then fruits as a floricane in year two and dies. Marion is a summer-bearing type, so there’s one crop a year, and all the new canes come from the crown. Unlike erect blackberries and raspberries, a Marion sends up no suckers from its roots, so it stays where you plant it. For that comparison, see our raspberry vs blackberry piece on which one spreads.

Once the plant is established, it carries both kinds of cane at once. The fruiting floricanes sit on the trellis. The new primocanes flop over at about 3 feet and keep growing along the ground, so OSU has you bundle them underneath the floricane canopy with wire hoops, stakes or tie tape. Training starts right after harvest. Cut the dead floricanes at the base, ideally by the end of August in the Willamette Valley, then train the new canes up. The primocanes keep growing from August until frost, and the trellis has to be clear for them.

When	Willamette Valley routine (OSU)	Colder or windier site (OSU)
Planting year	Train primocanes straight up to the top wire as they grow, bundled and wrapped around both wires	Leave the primocane bundle on the soil surface through winter
Spring and summer	Floricanes flower and fruit; new primocanes grow from the crown and are bundled below	Same
Right after harvest	Cut dead floricanes at the base; split primocanes into two bundles and loop them onto the wires	Cut dead floricanes at the base; keep the primocanes bundled low
November	Tuck or tie in the new growth once plants are dormant	Canes stay on the ground
Late February	Nothing to do	Train the canes onto the wires, well before bud break

The takeaway is that “where do the canes spend winter” is the one decision that differs between a mild and a cold site, and it’s the lever the next section pulls.

Three-panel diagram of the two-year blackberry cane cycle: primocane trained aside, floricane fruiting on the wires, then the old cane cut out at the base — Each cane lives two summers: it grows low and bundled in year one, fruits on the wires in year two, then is cut out at the base after harvest

Can You Grow a Marionberry in Zone 6?

Yes, but treat it as a protected crop rather than a hardy one. OSU’s cultivar table lists ‘Marion’ for Zones 6 to 9. The same OSU authors say trailing blackberries take damage below about 13°F. USDA zones are averages of each winter’s coldest night, so I lined the two up.

USDA zone	Average coldest night of the year	Compared with OSU’s 13°F damage point
6a	−10 to −5°F	18 to 23 degrees colder
6b	−5 to 0°F	13 to 18 degrees colder
7a	0 to 5°F	8 to 13 degrees colder
7b	5 to 10°F	3 to 8 degrees colder
8a	10 to 15°F	Straddles 13°F
8b	15 to 20°F	2 to 7 degrees warmer

In an average winter, only Zone 8b and warmer stay above 13°F. That doesn’t make OSU’s “Zones 6 to 9” label wrong. It means the label assumes the cultural practices OSU describes, and the USDA warns that its zones are averages, not the coldest night on record. A rare cold snap of a day or two can kill plants that thrived for years. One caveat on my arithmetic: OSU gives 13°F for trailing blackberries as a group, and I found no controlled trial that measured Marion’s own threshold.

What does help? Two West Virginia trials ran at Kearneysville, in Zone 6b, on a western trailing blackberry called ‘Siskiyou’, not on Marion.

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In the 2008 trial by Takeda and colleagues, a row cover raised nighttime lows by as much as 5 to 10°F after sunny days, and the effect was similar after overcast days. On sunny days it ran as much as 28°F hotter than open air. The cover significantly reduced winter injury and raised yield.
In the 2011 follow-up by Takeda and Phillips, canes laid horizontally close to the ground and covered gave 6.0 kg of fruit per plant in 2009. Horizontal canes with no cover gave 1.7 kg. Canes left vertical gave 2 kg or less, and the cover did nothing for them.

Together with OSU’s advice, that adds up to a Zone 6 routine:

Keep the canes off the wires in winter. After cane-out, leave the primocane bundle on the soil and train it onto the wires in late February, before bud break.
Add a cover. Where winter rainfall is low, OSU suggests straw over the canes, removed when buds start to break. Where it’s wet, use a row cover. OSU also mentions straw around the crown in some regions.
Time the cover to the forecast. OSU’s triggers are 20°F in November, 15°F in December or early January, or 20°F after a warm spell in late winter. Put the cover on in mid-afternoon and take it off after the cold passes. Because covers ran up to 28°F hotter in the sun, I wouldn’t leave one sealed over a warm spell.
Pick a sheltered spot. OSU advises avoiding sites exposed to high winds.
Watch the straw. Don’t bury the crown in organic mulch, which can promote rot. Don’t leave deep straw down through the growing season, because it invites voles and other rodents.

Even with all of that, expect a less reliable crop than Oregon growers get. If you want the lower-risk route, OSU lists the thornless trailing ‘Columbia Star’ for “Zone 5 or 6 to 9.” Our Zone 6 blackberry guide covers varieties chosen for that cold.

How Does ‘Marion’ Compare With Other Trailing Blackberries?

‘Marion’ wins on flavor and loses on thorns and cold hardiness. The table pulls the trailing blackberries in OSU’s home-garden list together, with a note on who each suits.

Cultivar	OSU zones	Thorns	OSU flavor	Best for / avoid if
‘Marion’	6 to 9	Thorny	Excellent	Best for jam, freezing and pies. Avoid if you can’t protect canes in winter or have kids running past the row.
‘Columbia Star’	5 or 6 to 9	Thornless	Very good	Best for colder or family gardens. Avoid in wet, heavy soil, where OSU says it may get root rot.
‘Hall’s Beauty’	6 to 9	Thornless	Good	Best if you want thornless maroon fruit and don’t need top flavor.
‘Boysen’	6 to 9	Thornless clones may revert to thorny	Excellent	A raspberry-blackberry hybrid with maroon fruit. See how to grow boysenberries.

If you haven’t settled on a trailing type at all, start with our comparison of erect, semi-erect and trailing blackberries.

How Do You Plant and Feed a Marionberry?

Plant it as early in spring as the soil can be worked, in full sun and fertile, well-drained soil. OSU says blackberries tolerate wet, heavy soil and partial shade, though shade lowers yield and fruit quality. The numbers below are OSU’s.

Task	OSU number
Planting depth	Roots 1 to 2 inches below the soil surface; cut bare-root canes to 6 inches
Spacing	3 to 5 feet between plants, 10 feet between rows, each grown as an individual
Water	1 to 1.5 inches a week once established; drip line with half-gallon emitters every 18 inches
Nitrogen, planting year	1 to 1.4 ounces of N per plant
Nitrogen, later years	1.5 ounces of N per plant a year, split in two (late March or early April in the Willamette Valley, then six to eight weeks later)
Cropping timeline	A small “baby” crop the year after planting, full production in year three
Picking	Every 4 to 7 days, when the fruit turns from shiny black to dull black

The dull-black cue matters because shiny black fruit is higher in acid and has less flavor and sweetness. Our dull-gloss test for blackberries covers it in detail, and the blackberry pruning guide covers the cuts. Keep berries dry until you eat them. Refrigerate them right after picking and skip the wash, since wet fruit decays faster.

What’s Wrong With My Marionberry? A Diagnostic Table

Winter cold is the most common problem outside Oregon, and its symptoms show up in spring as poor fruiting rather than dead plants.

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Symptom	Likely cause	Fix
Few fruiting laterals, uneven bud break, or laterals that start then collapse	Winter cold injury to buds and canes, worst at the cane tips	Next winter, train canes late and add a row cover on cold nights
Primocanes die in midsummer; laterals collapse just before or during harvest	Phytophthora root rot in wet, heavy soil	Improve drainage and remove infected plants; OSU singles out ‘Columbia Star’ among trailing types
Purple lesions up to 2 inches on canes, or small purple leaf spots turning brown	Purple blotch and Septoria leaf spot, which most trailing types are sensitive to	Usually no spray; good pruning, training and weed control are enough
Yellow spots on leaf tops and yellow fungal spots underneath on floricanes	Cane and leaf rust, after rain follows warm weather	Remove infected floricanes, rake fallen leaves, and don’t tie primocanes until leaves fall
Berries look fine but are soft, with larvae inside	Spotted wing drosophila, which lays eggs in coloring fruit	Fine exclusion netting; trailing types fruit early, so they’re less prone than late types
Gray fuzzy mold on fruit after rain or overhead watering	Botrytis fruit rot	Remove diseased fruit at once, use drip irrigation, pick before long rain
Galls at the crown; canes splitting open	Crown gall	Remove the plant, disinfect tools, buy certified disease-free plants
Pale green or yellow primocane leaves, mostly near the base	Nitrogen shortage	Feed 1.5 ounces of N per plant a year, in two splits

Frequently Asked Questions

Is a marionberry a bush or a vine?

Neither exactly. It’s a trailing blackberry whose canes can pass 15 feet and can’t support themselves, so it needs a two-wire trellis. Left alone, the canes sprawl across the ground.

Do marionberries have thorns?

Yes. OSU lists ‘Marion’ as thorny. If thorns are a dealbreaker, OSU lists thornless trailing options such as ‘Columbia Star’ and ‘Hall’s Beauty’.

Where are marionberries grown?

Mostly in Oregon, which has more than 90% of the world’s Marion acreage. About 4,500 acres there produce 28 to 33 million pounds, and over 95% of the crop is processed.

Can you grow a marionberry in Zone 6?

OSU lists ‘Marion’ for Zones 6 to 9, but trailing blackberries take damage below about 13°F, so Zone 6 needs winter protection. Keep the canes on the ground until late February and cover them in cold snaps.

How long until a marionberry plant fruits?

A small crop comes the year after planting, because the first-year canes fruit as floricanes in year two. Full production arrives in year three, at 10 to 13 pounds per plant.

Does a marionberry spread like a raspberry?

No. All of its new canes come from the crown, not from the roots, so it stays put. That makes it less invasive than erect blackberries, which sucker from the roots.

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