Why May Is the Perfect Time to Map Sunlight in Your Garden

Before you dig, plant, or plan this spring, take a moment to map the sun. Understanding how sunlight moves through your yard is one of the most important—and often overlooked—steps in creating a successful garden. In fact, May is one of the best times to observe these light patterns, especially before trees fully leaf out and change the game.

Whether you’re dreaming of a lush perennial bed, planting edibles, or adding new shrubs or annuals, sun exposure matters. Certain plants crave full sun to thrive, while others wilt without a little afternoon shade. Mapping your sunlight can help you choose the right plants for the right place—and avoid costly mistakes.

Why Sun Mapping Matters

Every plant has a sun preference: full sun, part sun, part shade, or full shade. These terms may seem vague, but they correspond to real hours of sunlight your garden receives during the day:

• Full sun = 6+ hours of direct sunlight

• Part sun/part shade = 3–6 hours of direct sunlight

• Full shade = Less than 3 hours of direct sun

Planting a sun-loving zinnia in a shady spot or a delicate hosta in the blazing sun can leave even experienced gardeners scratching their heads. That’s where sun mapping comes in.

How to Map Your Yard’s Sun Exposure

1. Choose a Clear Day in May

Set aside a sunny day to observe your yard. Bring a notebook, your phone’s camera, or print a basic sketch of your property.

2. Mark Key Times

Check and note the light conditions in different parts of your yard at these key times:

• 8 a.m.

• 12 noon

• 3 p.m.

• 6 p.m.

Look for areas that receive direct sunlight, dappled light, or are fully shaded. Repeat the process over two or three days to catch any variations due to buildings, fences, or trees.

3. Watch for Seasonal Changes

In early May, trees are just leafing out—so don’t forget that shady areas may become even darker by June. If you’re unsure, take note of nearby deciduous trees and imagine the change once they’re in full foliage.

4. Create a Simple Map

Draw a quick sketch of your yard and mark:

• Full sun zones (6+ hours): ideal for vegetables, herbs, annuals, and heat-tolerant perennials like lavender and coneflowers.

• Part sun/shade zones (3–6 hours): great for many perennials, impatiens, ferns, and woodland natives.

• Full shade zones (less than 3 hours): perfect for hostas, astilbe, heuchera, and ferns.

5. Use Tools If You Like

Prefer tech over sketchpads? There are sunlight tracking apps available, or you can even use time-lapse videos to see the sun’s arc.

What to Do with Your Sun Map

Once you know where the sun shines and for how long, matching plants to their perfect spots becomes easier—and more rewarding. At Nunan’s, we’re always happy to help you interpret your map and recommend plants that will thrive in your space.

Plus, you’ll save time, money, and effort by choosing plants based on real conditions, not just what looks good on the tag.

Visit Us at Nunan’s Florist & Garden Center

Need help finding the perfect plant for your newly mapped garden? Visit our experts at Nunan’s in Georgetown, MA. We grow 90% of our annuals and perennials right here, including over 60,000 Proven Winners each year—so you know they’re already suited to our local climate and light conditions.

While you’re here, grab a coffee at Café Sarina or enjoy a round of mini golf with the family!
🌱 Pro tip: Download our app for exclusive deals and seasonal gardening tips. New users get $5 OFF with code welcome: https://apjl.app/nunans