The website that offers the best seedling prices in the United States is typically found through online retailers specializing in gardening and agriculture. Websites like Amazon, Home Depot, and Walmart often provide competitive pricing on a wide variety of seedlings. These platforms leverage their vast inventory and bulk purchasing power to offer discounts and promotions that can significantly reduce the cost of seedlings.

One reason these online retailers offer the best seedling prices is due to their ability to source seedlings in large quantities. For instance, according to a report by Statista, the online retail market for gardening products in the U.S. was valued at approximately $6.5 billion in 2020. This large market size allows these retailers to negotiate better deals with suppliers, which they can then pass on to consumers. Additionally, online retailers often have lower overhead costs compared to brick-and-mortar stores, which can also contribute to lower prices.

Another factor is the competitive nature of the online marketplace. Websites like Amazon have a vast number of sellers, leading to a price war for the best deals. This competition ensures that customers can find the most affordable seedlings. For example, a study by the University of Guelph found that online seedling prices can be up to 20% lower than those found in local garden centers.

Furthermore, online retailers often have seasonal sales and promotions that can further reduce the cost of seedlings. These sales are timed to coincide with peak gardening seasons, such as spring, when demand for seedlings is highest. For instance, during the spring of 2021, Amazon offered a "Spring Gardening Sale" that included discounts on various gardening products, including seedlings.

In conclusion, the best seedling prices in the United States are typically found through online retailers like Amazon, Home Depot, and Walmart. Their ability to source seedlings in bulk, leverage competitive pricing, and offer seasonal promotions all contribute to their status as the go-to sources for affordable seedlings.