Zone 5 · Fruit Growing Guide

When to Plant Sunflower
in Zone 5

One of the most cheerful crops in the garden. Edible seeds and cut flowers. Direct sow only — sunflowers dislike transplanting. Great for attracting pollinators and beneficial insects.

Plant outdoors
May 15 – Jun 1
Start indoors
Direct sow
Last Frost
~Apr 15
Days to harvest
70–100 days
Difficulty
Easy
Plant now — Zone 5
Harvest window: Aug – Oct

Planting Calendar

In Zone 5, Sunflower should be planted outdoors May 15 – Jun 1, after the average last frost date of approximately Apr 15.

Good zone. Multiple varieties possible from branching to giant single-head.

Care Guide

Sunlight
Full sun · 6–8 hrs/day
Watering
Low
Spacing
12–24 inches
Soil
Well-draining, moderate fertility
Days to maturity
70–100 days
Soil pH
6.0–7.5
plant tip · Zone 5

Good zone. Multiple varieties possible from branching to giant single-head.

Feeding Schedule

How often
monthly
Feed type
balanced then high potassium
Key timing
switch to high-potassium at bud formation

Feed balanced fertilizer monthly. Switch to low-nitrogen, high-potassium feed when buds form for better head development.

Succession Planting

Sow every 2 weeks

Sow every 2 weeks from last frost through midsummer. Succession gives you a long season of blooms rather than all flowers opening at once.

Companion Planting for Sunflower

What you plant next to sunflower makes a real difference — some plants actively help, others compete or attract pests.

Grows well with
  • Cucumbers
  • Corn
  • Squash
  • Beans
Keep away from
  • Potatoes
  • Fennel

These guides get better when growers like you contribute. If something’s wrong or you’ve learned something worth sharing, we’d love to hear it.

What needs correcting?

What should it say?

Your zone (optional)

Thanks — we'll review this and update the guide if needed.

Your growing tip for Sunflower

Your name (optional)

Your zone (optional)

Tips are reviewed before publishing. Accepted tips earn you a Founding Grower badge when the plant app launches.

Thanks for contributing! We'll review your tip and be in touch before launch.

Common questions

In Zone 5, direct sow sunflower outdoors May 15 – Jun 1 after your last frost date of approximately Apr 15. Good zone. Multiple varieties possible from branching to giant single-head.
Zone 5 has an average last spring frost of approximately Apr 15 and a first fall frost around Oct 15. These dates vary by specific location — use your ZIP code in the plant app for precision based on the nearest NOAA weather station.
Good companion crops for sunflower include Cucumbers, Corn, Squash, Beans. Avoid planting near Potatoes, Fennel, which can compete for nutrients or attract pests.
Sunflower typically takes 70–100 days from transplant or direct sow to harvest in Zone 5. Expected harvest window: Aug – Oct.

Free app · iOS February 2028

Track your Sunflower in plant

Get a live traffic light for every crop in your garden — zone-aware planting calendar, real-time weather alerts, and a community of growers near you.

Be first to back on Kickstarter and lock in the founding price.

Sunflower in other zones
Crop Guides