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Purple plums growing on a branch
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When to plant plum trees in Oregon City and West Linn, OR

Plant plum trees in Oregon City and West Linn Mar 1 – Apr 26.

Easy Plant bare-root or potted trees

Difficulty
Easy
Sun
Full sun
Spacing
12 to 15 feet apart for dwarf or semi-dwarf trees
Planting depth
Graft union 2 to 3 inches above the soil
Frost
Hardy perennial; comes back every year
First harvest
First plums in three to five years

Why these dates

Oregon City and West Linn's typical last spring frost is March 18. As a hardy perennial, this crop doesn't need to wait for that date. In the west-side valleys, though, the soil usually isn't ready to work until about March 1.

West-side valleys. The Willamette Valley, Puget Sound and southern Oregon valleys. Long frost-free seasons, but soil stays cold and wet into May, so warm crops wait for warm soil, not just the last frost.

How to grow plum trees in Oregon City and West Linn

  1. Pick a sunny spot with soil that drains well, and mix in an inch or two of compost.
  2. Plant plum trees Mar 1 – Apr 26, 12 to 15 feet apart for dwarf or semi-dwarf trees. Graft union 2 to 3 inches above the soil.
  3. Water deeply through the first two summers. Prune lightly in summer, not winter, which lowers the risk of silver leaf and canker. Thin heavy crops so branches don't snap.
  4. Harvest: Pick when the fruit is fully colored, slightly soft and comes off easily. Prune plums for drying should hang until they wrinkle slightly at the stem.

Key numbers

Growing notes

What makes the difference in Northwest gardens, in plain language.

European or Japanese plums

European plums, including Italian prune and Stanley, bloom later and fruit on their own, which makes them the easiest choice for most Northwest gardens. Their dense, sweet flesh is great fresh, dried or baked. Japanese plums such as Shiro and Methley bloom earlier, have juicier fruit and ripen in mid-summer. Shiro sets a much better crop with another Japanese plum nearby, and Methley is a popular partner because it's partly self-fertile. In frost-prone spots, the earlier bloom of Japanese plums can get caught by a cold snap.

Why plums are pruned in summer

Plums and other stone fruits are prone to silver leaf and bacterial canker, which enter through pruning cuts in cool, wet weather. Cuts made in dry summer weather heal fast and stay clean. Prune lightly after harvest or in July, removing dead wood, crossing branches and tall upright shoots.

Heavy crops are common. Thin young fruit to 3 to 4 inches apart in early summer: the remaining plums grow bigger, brown rot spreads less between touching fruit, and branches are less likely to snap.

Harvest and brown rot

Brown rot is the main Northwest plum problem. It blights blossoms in rainy springs and turns ripening fruit into fuzzy gray balls that dry into mummies. Those mummies carry the fungus into next year, so pick them off the tree and the ground. Good airflow and thinning help a lot.

Italian prunes are sweetest when left to hang until they wrinkle slightly at the stem. Japanese plums soften quickly once ripe, so check every couple of days.

Common questions

When is the last frost in Oregon City and West Linn, OR?

Typically March 18. In 9 years out of 10, frost is over by April 11. These are 1991–2020 NOAA climate normals for Oregon City.

Is it too late to plant plum trees in Oregon City and West Linn?

The spring planting window runs through April 26. Potted plants can still go in later if you water them faithfully through their first summer. Fall planting also works well here.

How long until I can pick plum trees?

First plums in three to five years. Pick when the fruit is fully colored, slightly soft and comes off easily. Prune plums for drying should hang until they wrinkle slightly at the stem.

Do plum trees need a pollinator?

European plums like Italian prune and Stanley are self-fertile and fruit fine alone. Japanese plums such as Shiro do much better with another Japanese plum nearby.

What's the difference between a prune and a plum?

A prune plum is a European plum with dense, sweet flesh that dries well without fermenting at the pit. Italian prune is the classic Northwest variety, and it's just as good eaten fresh.

Why are my plums rotting on the tree?

That's usually brown rot, a fungus spread by wet weather. Thin the fruit so plums don't touch, remove any shriveled mummies from the tree and the ground, and pick promptly when ripe.

Also plant in Oregon City and West Linn around the same time

Planting dates for plum trees in nearby areas

Full planting calendar for Oregon City and West Linn · Plum trees in every city