To help you spend less green, our Ratings Tables evaluate local garden centers for the prices they charge.

Our undercover shoppers checked prices at each listed store or chain for 14 different plants, such as a lavender in a #1-size container and a knockout rose in a #3 container.

The price comparison scores on our Ratings Tables show how each store’s prices for the items it stocked compared to the average prices at all surveyed garden centers for the same items. (Because we found generally consistent prices for the large chains, we used a single chain-wide average price for each item.) The scores are adjusted to a base of $100. Thus a store with a price comparison score of $110 had prices 10 percent higher than the average of all stores’ prices for the same items.

For the limited selection of plants they sell, Home Depot and Lowe’s did very well on price. Home Depot’s prices averaged 24 percent below the all-store average for comparable items, and Lowe’s averaged 19 percent below the all-store average. Unfortunately, both chains received low ratings on our survey question “quality of products.”

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The table below reveals tremendous store-to-store price variation—possibly more than for any other type of business we cover. For almost all of the 15 different plants we checked, the highest price was more than twice the lowest price; in some instances, the highest price was more than three times the lowest price.

When using the price comparison scores, keep in mind that we could not compare prices on identical products; although two stores might sell the same type of azalea with similar spreads, for example, the plants’ health or fullness of foliage may be distinctly different.

It is important to note that in this field—unlike most we cover—there is a correlation between price and quality. A store with high ratings on our customer survey for “quality of products” is more likely than not to have a higher-than-average price comparison score. Fortunately, however, some stores that rated high on our quality measures also had below-average prices.

But this price-quality tradeoff leads many plant-buying consumers to shop at more than one spot. Many of our members rate more than one garden center, reporting that they buy inexpensive annuals and other items that only last for a short time from Home Depot, Lowe’s, grocery stores, etc., but purchase expensive perennials at nurseries that have high standards for quality.