How to Navigate Nursery Containers

When I first started container gardening I didn’t pay a lot of attention to container size. I just brought the plants home and put them in a bigger pot than the pot I bought them in. However, one summer I was complaining to my aunt about how my tomatoes were never productive and she asked me “Well you know tomatoes need a 5 gallon pot right?” That one question changed the way I garden. My tomato plant that summer was the most productive I had ever had.

If you are a beginner container gardener I encourage you to not be like me, and as you’re reading various growing guides I implore you to write down the recommended container size for each plant. Unfortunately, you will probably learn very quickly that there is a lot of variation in how gardeners and nurseries label their pots.

If you are looking at growing cayenne peppers for example, you may see one growing guide that recommends using an 11 liter pot. Another growing guide may say use a 3 gallon container. A third may say use a 10 inch pot and a fourth may say use a #3 container. In this scenario the words container and pot are interchangeable and each of those 4 sizes represents the same size pot even though none will hold a full 3 gallons of soil and none will be exactly 10 inches in diameter or height.

In another scenario, you may be reading about growing tomatoes on your patio and may find that folks (myself included) recommend housing mature plants in a 5 gallon container. But then when you go to your local big box store or nursery all of the pots are in inches. Which one do you buy?

3 “quart” nursery pots with different dimensions.

I struggled with awkwardly and frantically googling container sizes or bringing a tape measure with me when shopping for pots for years. Finally though, I scoured the internet and put together a table to guide me when I’m shopping for new containers.

I’ve included the table below and I hope it helps you as much as it will be helping me. Please note that these translations between gallon size, liter size, inch size and # size are not exact but represent the most common parallels between container sizes. Also, not all container sizes have equivalents in the other naming styles.

Good luck and enjoy the chaos!

Nursery Container Cheat Sheet

Gallon Size	Liter Size	Inches (Diameter)	# Container	Common Dimension Ranges	Common Liquid Volume Ranges	Common Dry Soil Volume
Pint	0.5 L	3-4 inch		3 ¼-3 ½ wide x 3 ½ – 4 tall		0.1 ft 3
Quart	1 L	5-6 inch				0.3 ft 3
½ Gallon (2.5 qt)				6 – 6 ½ wide x 6 – 6 ½ tall
1 Gallon	4 L	7-8 inch	#1	6-7 ½ inches wide x 7 inches tall	0.7 – 1.1 gallons	0.13 ft3
2 Gallon	7.5 L	8.5 inch	#2	8 ½ -9 inches wide x 8 ½ inches tall	1.4 – 2.1 gallons	0.26 ft3
3 Gallon	11 L	10 inch	#3	9/12 – 11 inches wide x 9 ⅛ – 9 ½ inches tall	2.6 – 3.2 gallons	0.40 ft3
4 Gallon	15 L	11 inch				0.53 ft 3
5 Gallon	19 L	12 inch	#5	10 ½ – 12 inches wide x 11 – 12 inches tall	3.4 – 5.4 gallons	0.66 ft 3
7 Gallon	26.5 L	14 inch	#7	12 ¾ – 14 inches wide x 11 ½ – 14 ½ inches tall	5.8 – 7.7 gallons	0.94 ft 3
10 Gallon	38 L	16 inch	#10	15 ¾ – 16 inches wide x 15 inches tall	9 – 11.5 gallons	1.33 ft 3
15 Gallon	57 L	18 inch	#15		12 – 16 gallons	2.0 ft 3
20 Gallon	75.5 L	21 inch	#20		19.6 – 22.3 gallons	2.67 ft 3
25 Gallon	94.5 L	24 inch				3.34 ft3