When to plant oregano in Ontario, OR

Plant young oregano plants in Ontario Apr 1 – May 27.

Easy Plant young plants

Difficulty: Easy
Sun: Full sun
Spacing: 12 to 18 inches apart
Planting depth: Plant at the depth it grew in the nursery pot
Frost: Handles light frost
First harvest: Pick lightly the first year, freely after that

Why these dates

Ontario's typical last spring frost is April 21. As a cool-season crop that handles light frost, this crop doesn't need to wait for that date. In the Columbia Basin and low eastern valleys, though, the soil usually isn't ready to work until about April 1.

Columbia Basin and low eastern valleys. Hot, dry summers and quick spring warm-up. Warm crops go in earlier than west of the Cascades, and irrigation matters more than rain.

How to grow oregano in Ontario

Pick a sunny spot with soil that drains well, and mix in an inch or two of compost.
Plant young oregano plants Apr 1 – May 27, 12 to 18 inches apart. Plant at the depth it grew in the nursery pot.
Water sparingly once established. Rich soil makes the flavor milder, so skip the fertilizer.
Harvest: Cut stems just before flowering, when flavor peaks. Dry bunches upside down in a shady, airy spot.

Key numbers

6.0–8.0Soil pH
Rarely, if everFertilizer
Just before floweringBest flavor
Every 3–4 yearsDivide

Growing notes

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

Lean soil, strong flavor

Oregano's flavor comes from aromatic oils in the leaves, and plants make the most of them in full sun and lean, well-drained soil. Rich soil, fertilizer and lots of water grow big, leafy plants with a milder taste. Once established, water only in long dry spells.

Like most Mediterranean herbs, it dislikes soggy winter soil, so give it a raised or well-drained spot west of the Cascades. It's hardy across the Northwest, though Greek oregano is a little less cold-tolerant in the harshest eastern winters.

Pick the right plant

The word oregano covers plants with very different flavors. Greek oregano has the strong, peppery taste most cooks want. Many seed packets labeled simply oregano grow a mild, ornamental type with little flavor. The safest approach is to buy a plant and rub a leaf before you buy: good culinary oregano should smell sharp and taste almost spicy.

Golden oregano is milder and grown mostly for its bright foliage.

Harvesting, drying and dividing

Cut stems just as flower buds form, when flavor peaks, and dry bunches upside down in a shady, airy spot. Unlike many herbs, dried oregano keeps much of its flavor. Cutting back by half in early summer gives a second flush of leaves for a later harvest.

After three or four years, clumps get woody in the middle. In spring, dig the clump, cut it into a few pieces with healthy roots and shoots, and replant the strongest ones.

Common questions

When is the last frost in Ontario, OR?

Typically April 21. In 9 years out of 10, frost is over by May 8. These are 1991–2020 NOAA climate normals for Ontario Municipal Airport.

Is it too late to plant oregano in Ontario?

The spring planting window runs through May 27. Later plantings tend to struggle in summer heat.

How long until I can pick oregano?

Pick lightly the first year, freely after that. Cut stems just before flowering, when flavor peaks. Dry bunches upside down in a shady, airy spot.

Why does my oregano have no flavor?

Either it's a mild ornamental type, or it's growing in rich, damp soil or shade. Greek oregano in full sun and lean soil has the strongest taste. Harvest just before it flowers for the best flavor.

Is oregano the same as marjoram?

They're close relatives in the same plant group. Marjoram is sweeter and milder and less cold hardy, while oregano is more pungent and a tough perennial in most of the Northwest.

Should I let oregano flower?

For the best leaves, harvest before it flowers. But the flowers are a favorite of bees and other pollinators, so many gardeners let part of the plant bloom and cut the rest for the kitchen.

Also plant in Ontario around the same time

Planting dates for oregano in nearby areas

Baker City, OR Apr 27 – Jun 22
Pendleton, OR Apr 1 – May 27
The Dalles, OR Apr 1 – May 27
Hood River, OR Apr 1 – May 27
Hermiston, OR Apr 1 – May 27
La Grande, OR Apr 15 – Jun 10

Full planting calendar for Ontario · Oregano in every city