Rock Gardeners' Last Resort

(When the search engines fail, find your answer here.)
Why?Criteria for Inclusion
Sites Describing Plants
Calflora
Collaboration of US Government and California organizations
Plants of California
Photos, Plant Descriptions, Habitats, Taxonomy
Comprehensive collection of California species, both native and alien. Remarkable achievement. Extensive photo collection. Links to other California resources.  More about this. Typical results: Castilleja affinis
Clematis on the Web
University of Hull
Clematis
Photos, Culture, Plant Descriptions
Need we say more.  More about this.
Flora of China
Several Chinese and Western Institutions
Plants of China, SE Asia
Plant Descriptions, Habitats, Distributions, Taxonomy
Magnificent and incomplete. If the species you are looking for is in one of the 49 families written up, then this link gives everything. If not, use the checklist below.  More about this. Typical results: Primula algida
Flora of North America
Flora of North America Association
Plants of North America
Photos, Plant Descriptions, Habitats, Taxonomy
The ultimate source for North American plants, but so far including only the ferns, conifers, a few monocots, and the dicot orders Magnoliidae and Hamamelidae. These latter are heavily populated with trees and shrubs, but rock gardeners will find the Ranunulaceae and Papaveraceae of interest.  More about this.
Harkness Seedlist Handbook
North American Rock Garden Society
Rock Garden Plants
Plant Descriptions
Brief descriptions and origins of 20,000 plants. Typical results: Dodecatheon
National PLANTS Database
United States Department of Agriculture
Plants of the USA
Photos, Culture, Plant Descriptions, Habitats, Taxonomy
The PLANTS Database is a single source of standardized information about plants. This database focuses on vascular plants, mosses, liverworts, hornworts, and lichens of the U.S. and its territories. The PLANTS Database includes names, checklists, automated tools, identification information, species abstracts, distributional data, crop information, plant symbols, plant growth data,plant materials information. Slow site. Typical results: Mimulus primuloides
Plants for a Future
Plants for a Future
Herbals and Others
Culture, Plant Descriptions, Habitats, Taxonomy
"Plants For A Future is a resource center for rare and unusual plants, particularly those which have edible, medicinal or other uses." Not all or even most are rare and unusual but there are 7000 entries with extensive data, notably propagation, on each.  More about this. Typical results: Anemone
Rock Garden Plants Database
Dr. Pavel Slabý
Rock Plants, Alpines
Photos, Culture, Plant Descriptions, Taxonomy
Splendid list of rock garden plants with description, cultivation, propagation, and often photos too. Omits all monocots, ferns. Typical results: Saxifraga marginata
Mainly about Culture
Alpine-L Discussion Archives
Harry Dewey and others
Rock Garden Plants
Culture, Plant Descriptions
Seven years and 1000 participants must have said something about your favorite plant.  More about this. Typical results: Spigelia marilandica
Arisaema-L Discussion Archives
George R Stilwell, Jr. and others
Arisaema
Culture, Plant Descriptions, Taxonomy
Friendly to Arisaema.  More about this. Typical results: Arisaema candidissimum
Penstemon-L Discussion Archives
Louise Parsons and others
Penstemon
Culture
How to germinate and grow on Penstemon species and cultivars.  More about this. Typical results: Penstemon whippleanus
Plant Facts
Ohio State University Cooperative Extension
Ornamental Plants
Photos, Culture
Photos and cultural info from many Cooperative Extension databases. Typical results:
Rooting Database
U. of California, Davis, Environmental Horticulture Department
Woody Plants
Culture
This database is a compilation of published experiments in rooting woody plants. Typical results: Chamaecyparis obtusa
Shadegardens Discussion Archives
List Owners: no response
Woodland Plants
Culture
Shadegardens list exists to discuss the cultivation and propagation of shade plants. Less technical than Trillium-L and spreads beyond the bounds of rock gardening. The search interface is awkward. Typical results: corydalis AND flexuosa
Trillium-L Discussion Archives
Jim McClements and others
Trillium and Woodland Plants
Culture
Mostly Trillium, but other plants welcome.  More about this. Typical results: Trillium ovatum
Photos
Carnivorous Plants
Rick Walker
Photos and Nomenclature
Photos, Taxonomy
Sarracenia and 3000 relatives (counting cultivars). Typical results: Sarracenia flava
Vascular Plant Image Gallery
Texas A&M Department of Biology
Vascular Plants
Photos
There are lots of photos here:. flowers, fruit, habit, plant parts. Typical results: Lupinus texensis
Nomenclature
A Synonymized Checklist of the Vascular Flora of the United States
Texas A & M University
United States, Puerto Rico, V.I.
Distributions, Taxonomy
A Synonymized Checklist of the Vascular Flora of the United States colloquially known as Kartesz. A primary source for nomennclature and synonymy.  More about this. Typical results: Saxifraga flagellaris
Flora Europaea
RBG Edinburgh
Plants of Europe
Taxonomy
Just taxonomic and distribution data. The database seems to be comprehensive as to species, but there is no statement relating to the number of entries or completeness. The user interface is primitive.  More about this. Typical results: Hepatica
Flora of China Checklist
Missouri Botanical Garden
Plants of China
Taxonomy
The checklist has 30,000 entries, i.e., a complete list, whereas the Flora itself is considerably smaller in scope but provides more descriptive material. Typical results:
Global Plant Checklist
International Organization for Plant Information
Valid Names
Taxonomy
A source for verification of plant names, as of January 2000 including 200,000 vascular plants with extensions planned.  More about this. Typical results:
GRIN Taxonomic Database
USDA National Plant Germplasm System
Plants of the World
Taxonomy
Extensive taxonomic and distributional data - 37,000 taxa. Economic plants are a priority but there is much more. Amazing slew of bureaucratic acronyms.  More about this. Typical results: Sedum spathulifolium
Intermountain Flora
New York Botanical Garden
Plants of the Great Basin
Photos, Taxonomy
Taxonomic info and images of the type specimens from the NYBG Herbarium. As of January, 2000 the images of interest to rock gardeners are in the Ericaceae. Shame it's not Intermountain Flora itself.
International Plant Name Index
RBG Kew, Harvard University Herbaria, and the Australian National Herbarium.
Valid Names
Taxonomy
Valid names from three institutions.  More about this. Typical results: Gentianella
L'Index Synonymique de la Flore de France
Institut National de la Recherche Agronomique
France
Distributions, Taxonomy
Synonomy for the flora of France, 62,000 names. Search interface is primitive.  More about this. Typical results: Ramonda
Plant Name Finder
National Gardening Association, USA
Common/Botanical Names
If you know the common name and want the scientific (or vice versa) this is the place. Common names are English only.
RBG Kew Plant Families
RBG Kew
Vascular Plants
Taxonomy
Families, Genera, Authors. Synonomy for genera, but not families. Typical results: Polemoniaceae
w3Tropicos
Missouri Botanical Garden
Plants of the World
Taxonomy
w3Tropicos provides access to the Missouri Botanical Garden's nomenclatural database and associated authority files. Information is available for over 750,000 scientific plant names. The records frequently have links to other associated names, types, synonymy, and bibliographic references. Typical results:
Directories
Database of Plant Databases
International Organization for Plant Information
Databases
Taxonomy
A collection of taxonomic databases and herbarium collections, some on the net and some not. If you are searching for a family or genus or geographical area, this can be a good starting point.  More about this. Typical results:
Glossary of Botanical Terms
GardenWeb
Botanical Terms
3700 definitions, comprehensive and cross-linked, from abaxial to zygote. Typical results: filiform
Horticultural Dictionary
National Gardening Association, USA
Gardening Terms
Has dibble and 15,000 other terms. Typical results:
HortiPlex Plant Database
GardenWeb
Information Sources, Vendors
Photos
Links to many databases, vendors, and a collection of their own images. This is a meta search engine.  More about this. Typical results: Lobelia cardinalis
RHS Plantfinder
Royal Horticultural Society
UK Sources/Nomenclature
Taxonomy
Sources for plants, but only in the UK. Also a check for valid names, especially cultivars, listed even when there are no sellers. Typical results: Hosta venusta

A quarterly update of new resources is available. If you can use a regular infusion, replace the obsessive plant nut's email address with your own.

This site is the idiosyncratic view of Tom Stuart.
Rock Gardeners' Place Comments, Too (remove the spaces in the email address)