North Shore Plant Club
Have you ever picked up a plant in a pot labeled “1 gallon” and thought, "There is no way I could pour a gallon of milk in here!"? If so, you’re absolutely right!
In the gardening world, a “1 gallon pot” is not a true liquid gallon. Understanding why requires a little horticultural history.
The Birth of the Trade Gallon
After World War II, the United States had a surplus of metal one‑gallon cans that had been used for food storage. Nurseries, always resourceful, snapped them up and began growing plants in them. Plants grown in those cans were marketed as "1 gallon plants" and quickly became gardener favorites.
As the nursery industry evolved, growers shifted from metal cans to lightweight plastic containers. Rather than preserving exact liquid volume, manufacturers focused on making pots that worked better for roots, stacking, automation, and shipping. But the name had already stuck in customers' and nurseries' minds. "1 gallon" became a trade size, not a measurement. It was shorthand for a certain class of plant—its age, root development, and readiness for sale—rather than the amount of soil in the pot.
How Big Is a "1 Gallon" Pot, Really?
A true U.S. liquid gallon is 231 cubic inches. Most standard nursery #1 containers hold closer to 0.7–0.75 gallons—roughly 3 quarts of growing media. That difference comes from practical design choices:
"1 gallon" pots from various nurseries vary slightly from one another. Similarly, in their marketing material and inventory, nurseries call these pots a wide variety of names, including 1 gal, 1G, #1, #1 gallon, and literally 1 gallon. Because this is confusing to just about everyone, the Plant Club groups these types of pot sizes together on the website with a common name so that you don't need to try to figure out which one of many different nurseries' approximately one gallon pots you actually want to buy!
By the way, none of the other plant pots are exactly the size that you would think, either. Here are some of the common plant pot sizes and what they really mean.
Why the Industry Keeps Using These Sizes
We agree. Using a size which already has a precise meaning and assigning it a different value is indeed a bit misleading! But for growers and landscapers, trade sizes provide consistency. A "#1" container signals an expected plant size and maturity, even though the exact pot dimensions may vary slightly by manufacturer.
More importantly, pot size in the nursery industry is tied to plant age and root system development, not soil volume. A perennial grown for a season in a #1 container has a predictable size, performance, and price point. Switching to true volume labeling would add confusion without improving plant quality.
What This Means for Gardeners
We try very hard to source exactly what you’d like, but sometimes growers run out of plants! While this variety is a great deal at the price shown, we know that it has limited availability. If you want the plant even if it might be more expensive, or in a different size or quantity -- after you place your order, just send us a quick note at help@northshoreplantclub.com. Then, we’ll try to get you some version of this from one of our growers. And if we can’t get it from anywhere, of course, we’ll send a refund!
Plants which are well-adapted to our local climate are most often field-grown (outside). Field-grown plants are generally cheaper and have the advantage of already somewhat acclimated to our cold winters, but that means they’re not artificially far along in the spring and tend to bloom at the normal time in our area.
Spring annuals and tender perennials are typically grown in Greenhouses so they can be ready and luxurious exactly when customers want them. Some perennials are also “forced” into early bloom in greenhouses. In May, there can be a very big difference between field-grown and greenhouse-grown plants of the same type. The latter typically look good right away (so they’re a great choice where that’s important), but we typically pay a premium for it.
The cost of this recipe's ingredients will vary depending on the season and the sizes and varieties you select.
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