You don’t have to buy all your plants at local garden centers; various websites and catalogs sell plants by mail. But should you deal with them?

There are two main advantages to buying by mail. First, plants can be less expensive (even including possible shipping costs). Second, catalogs and websites may sell unusual plants unavailable at local nurseries.

But there are also disadvantages to mail-order and buying online. First, you usually get bare-rooted plants, which can be planted only during the dormant season (before tree buds begin to swell). Second, you usually can’t get larger plants. Third, if you are dissatisfied, it’s a hassle to repackage them and send them back. Finally—and most important—you can’t see in advance exactly what you will be getting or select particular specimens. The plants you get may bear little resemblance to the beautiful pictures in the catalog or on the website.

If you decide to deal with internet or mail order firms, choose companies whose catalogs or websites provide the most precise and detailed descriptions. Catalogs that use only age to describe a plant’s size and fullness leave much to be desired. For a large directory of online sellers, along with customer reviews, visit The Garden Watchdog section of Dave’s Garden.

If you purchase plants via a mail order catalog or online, keep these tips in mind:

Be prepared. You’ll need to plant whatever you buy shortly after it arrives. Make sure the planting site is set, and have mulch ready, along with needed fertilizers.

Don’t leave plants trapped inside their packages very long. Open right away, and put the plants in a protected and shady place until you’re able to plant them.

Read carefully. Because nearly all mail order plants are dormant, you won’t really know if they are healthy until the growing season begins. Be sure to take a close look at the company’s guarantee and return policy.

Be patient. Nearly all photos in catalogs and online showcase mature plants at peak bloom. Yours may take a couple years to get there. Plus, most perennials won’t bloom the first year.

Many catalogers automatically substitute another plant if the one you ordered is out of stock. If you’re not interested in a substitution, make sure to state that clearly in the order.

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