Gardeners are not a bunch to be trifled with.

Scan through user reviews of the many gardening-related apps and you start to get a feel for this group’s exacting standards and their impatience with dilettantes. Software engineers who create these apps may know a good market when they see one, but judging from the reviews, many of them apparently know little about gardening.

Fortunately, a few apps for both Android and Apple users have generated positive reviews and the even better news is that two of the better ones are free.

The Gardening Guide from Mother Earth News (free on Apple and on Android, as Garden Guide), Gardening How-To (free on iPad and Android) and Landscaper’s Companion — Gardening Reference Guide ($6 on iPad and iPhone, $5 on Android) are all worth downloading.

The Landscaper’s Companion wasn’t created by a gardener, but the app’s developer, Dave Stevenson, and his researchers have landscaping and gardening experience with botanical gardens and the United States Department of Agriculture, among others.