Will your window box actually feed you?

Enter your box size, sunlight, and zone. Get honest weekly yield estimates for herbs, greens, and strawberries. No guesswork.

Start Planning

Your Window Box Setup

Standard boxes are 24–48 inches
Herbs need 6", strawberries need 10"+
6 hours Count hours when sun directly hits the box

How this planner works

1

Enter your box

Length, depth, and sun direction determine how many plants fit and how well they grow. A 36"×8" box facing south is the sweet spot for most herbs.

2

Pick your climate

Your USDA zone controls the growing season length. Zone 3 gets about 12 weeks of warm weather. Zone 9 can grow almost year-round.

3

See real numbers

Yields are based on published container-garden data and adjusted for small spaces. We show weekly ounces, not optimistic-per-plant claims.

4

Plan your season

The calendar tells you when to start seeds indoors, transplant, and expect first harvests. Save your setup and come back each season.

Real apartment scenarios

Here's what actual setups produce. These are based on common apartment configurations.

Studio, south window

Box size
24"×6"
Sun
8 hrs south
Weekly yield
2.1 oz herbs
Monthly savings
$8–12

Enough basil and chives for daily cooking. Not a grocery replacement, but fresh herbs taste better than dried.

One-bed, balcony rail

Box size
48"×8"
Sun
5 hrs east
Weekly yield
4.3 oz mixed
Monthly savings
$15–22

Lettuce, mint, and parsley do well here. You'll cut salad greens twice a week in peak season.

Two-bed, fire escape

Box size
48"×12"
Sun
7 hrs south
Weekly yield
7.8 oz mixed
Monthly savings
$28–40

This is where it gets serious. Deep box, full sun. You can grow strawberries, lettuce, and herbs with real volume.

High-rise, west glass

Box size
36"×6"
Sun
4 hrs west
Weekly yield
1.4 oz herbs
Monthly savings
$5–9

Limited light means slower growth. Stick to mint and parsley. Basil will struggle without more hours.

Common mistakes that kill yields

Shallow boxes

Anything under 6 inches deep dries out fast and stunts roots. Herbs survive but produce half what they should. Go 8 inches deep if you can.

Overcrowding

It's tempting to pack in seedlings. Crowded plants compete for light and water. You get more total weight with fewer, healthier plants.

Wrong crops for the light

Tomatoes and peppers need 8+ hours. In a 4-hour sun spot, you'll get leggy plants and zero fruit. Match the crop to your actual conditions.

No drainage

Boxes without holes drown roots. Drill or punch drainage holes before planting. Add a saucer below to protect your sill or railing.

Skipping soil refresh

Container soil breaks down after one season. Mix in compost or replace half the soil each spring. Old soil holds less water and fewer nutrients.

Ignoring wind

High floors get wind that dries soil and snaps stems. Wind-exposed boxes may need daily watering. Place taller plants on the windward side as a shield.

Questions people actually ask

What counts as a "good" sun direction?
South-facing gets the most light in the Northern Hemisphere. East and west get half-day sun. North-facing boxes only work for shade-tolerant crops like mint or parsley, and yields drop sharply.
Can I use this for indoor windowsills?
Yes. Bump your sun hours up by 1-2 if you have a bright south-facing window. Indoor boxes avoid wind and pests, so yields can be slightly higher than outdoor estimates.
Why are strawberry yields so low?
Strawberries need depth and space. A standard 6-inch-deep window box supports only a few plants, and they spread. You'll get some fruit, but not enough to replace store-bought pints.
How do I share my setup?
Click "Copy Link" to get a URL with your box settings encoded. Paste it anywhere or bookmark it for next season.
Are these yields per plant or for the whole box?
All numbers are for the total box harvest per week, assuming proper spacing. We calculate how many plants fit, then multiply by per-plant averages from container-garden research.
What about fertilizing?
These estimates assume you feed plants every 2-3 weeks with liquid fertilizer. Unfed container plants produce 30-50% less. Use a balanced organic feed or fish emulsion.