When to Plant Parsnips: Seasonal Timing Explained

Parsnips are a cool-weather root crop that reward patience. In my Sonoma Valley garden—where I grow year-round in raised beds and mounded rows—I’ve learned that parsnips succeed best when planted at just the right moment. Timing influences everything: germination, root development, and flavor. Here’s how to choose the right planting window wherever you garden.

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Parsnips Need Cool Weather From Start to Finish

Parsnips grow best when temperatures are consistently cool. They need a long season—100 to 120 days—to size up, and the flavor improves after exposure to autumn frost. Heat causes misshapen, fibrous roots, so starting at the optimal time is key.

Soil Temperature: The Most Reliable Indicator

Parsnip seeds germinate slowly, and warmth matters—but not too much warmth.

Ideal soil temperature for germination: 50–70°F (10–21°C)
Minimum germination temperature: 45°F (7°C)
Temperatures above 75°F (24°C) can stall or prevent germination entirely.

From my experience, parsnip seed sown into soil that’s below 50°F takes much longer to sprout—but it will still germinate as long as nighttime temperatures aren’t freezing. If the soil is above 70°F, I’ve had patchy rows and sparse emergence.

Because parsnip seed is naturally short-lived, I always use fresh seed each year to improve germination.

When to Plant in Spring

Spring sowing is the most common.

Cool-Climate Gardens (zones 3–6)

Plant 2–4 weeks before your last spring frost.
Cold soil will slow germination, but the cool season that follows is ideal for root development.

Mild or Maritime Gardens

Plant as soon as the soil can be worked and has warmed to at least 45–50°F.

My experience:

In Sonoma’s early spring, the soil warms quickly. I’ve had the best success sowing in late February to mid-March, once the soil consistently reads 50–55°F. Earlier sowings gave spotty germination; later sowings pushed the crop into summer heat, causing forked roots.

When to Plant in Summer for a Fall or Winter Harvest

In regions with hot summers, summer sowing can be tricky.

Warm-Summer Climates (zones 7–10)

Plant 90–110 days before your average first fall frost.
Aim to sow when daytime temperatures drop below 85°F and soil cools to 70°F or below.

My experience:

Because Sonoma summers are warm, I avoid sowing parsnips after April. Whenever I’ve tried June or July sowing, even with shade cloth, the soil stayed too warm and germination was poor. If you live in a hotter climate, fall-sown parsnips may be a better option.

When to Plant in Fall (Mild-Winter Climates Only)

Where winters are cool but not freezing (zones 9–10), parsnips can be sown in fall for a late-winter or early-spring harvest.

Sow when soil temperature dips to 60–70°F.
Ideal sowing window: September–October.

I’ve had beautiful late-winter parsnips by sowing in late September, allowing them to grow slowly through winter’s cool weather.

Tips From Years of Growing Parsnips

Use very fresh seed—the fresher the better.
Sow directly; parsnips dislike transplanting.
Keep the top inch of soil moist for 2–3 weeks.
Germination can take 14–21 days. I often lay a board over the seed row to hold moisture, removing it as soon as sprouts appear.
Mulch lightly once seedlings are up to prevent soil crusting and drying.

Final Thought

After growing parsnips for decades, my best crops always come from sowing early—right as soil reaches 50°F—and letting the roots develop through the cool season. With the right timing, parsnips will reward you with sweet, creamy-textured roots through fall and winter.