Revised or new content links marked in red
Cultivar Registers:
2020 Woody - 2018-19 Woody H-M - 2018-19 Woody A-I - Coleus - Hardy Herbaceous Perennials
Cultivar Registration: About OROC - Email us your new cultivar data - Woody Plant Long Form II
Resources: cultivar registration - encyclopedias - cultivar conservation - plant identification - Virtual Arboretum - nursery catalog links - Cultivar-TV 
Nursery catalogs: Cultivar250 top catalogs - Gilbert Digital Catalog (62,000+) - Internet Nursery Catalog Archive (INCA) 
Order encyclopedia:
Hatch's Cultivars of Woody Plants 2021-2022 - Hatch's Perennials - Hatch's Interior Plants
New Free ebook: Taxonomy Of Ornamental Plants by Larry Hatch: 172-page PDF guide to nomenclature, identification, and classification of landscape and floricultural plants.
Videos: The Juniper Society - Genus Variations 
Contact:, be sure to include a very specific topic in the subject line
HIP fast access buttons: push any of the buttons above for immediate load of the page or PDF file. They're 100% free. More are coming.

COOL CULTIVARS: New and Rare Houseplant Varieties hosted on YoutTube

New cultivars of non-hardy or interior landscape type (house plants, tropicals, conservatory vines, less hardy bulbs, aroids, non-hardy ferns, bromeliads, cacti, succulents, palms, selected bedding annuals, Begonia, Coleus, and more) are being registered through the new online Hatch's Interior Plants (HIP) enyclopedia now offered as an ad-supported and Patreon-funded content free to the general public. New cultivars and new cultivar groups are being posted in the files with the existing material for a tight, integrated, and uniform presentation under each species.

To register a new woody plant cultivar please complete this form. Click here or the logo above. Copy the text portion to an open email compose screen, fill out, and send.

Click cover above for the latest 231 new cultivars of trees, shrubs, vines, and conifers from around the world.

New for December 2019 is the International Registerof Coleus Cultivars, now free in the public interest from the
International Coleus Society (ICS). This reference has over 1600 cultivars described and with illustrations and high-res images when possible. These cultivars were introduced from 1858 to 2020. The ICS has been concerned that some names are being applied in commerce and among collectors for 2-4 different clonal and seed strain entities, causing more confusion. Some trademark names are also the same epithet(s) as existing, established cultivar names, adding even more chaos. Besides trying to sort out the various origins of clones and names, the ICS wants this document to discourage future homonyms in the trade. In other words, "that name is taken...let me pick a better one". If you wish to support this project please join the ICS or subscribe to any of the Encyclopedia. The ICS has more than 10 advanced, members only projects you can join including visual analytics, cultivar ID, landscape practice, phyllometric taxonomy, cultivar history studies, breeding and genetics, germplasm conservation, Coleus Art, and Cultivar Groups.

Click the icon above or here to load the IRCC menu. 

Effective 1 January 2020 OROC cultivar registrations will be published once per year as in the categories of woody plants, hardy herbaceous perennials, and interior and tropical plants with all genera in one volume. As always these will be in PDF format and 100% free to download and share under OROC Data Sharing rules.
The next free volume is slated for Spring 2020. For more frequent updates, our Cultivar Encyclopedia subscribers (who fund 90% of OROC) can receive frequent updates, as often as once a week, at no additional charge through a link on their menu pages. This new program is called OROC+NOW and is similar to the "working registers" seen in the past, showing additions as they come to us with only the least bit of delay for verification. This is our way of rewarding our absolutely necessary and loyal sponsors and also motivating new plant developers to share data with a rich marketing base to a virtual "Who's Who" in ornamental horticulture and many thousands of revoted collectors, growers, and curators with real buying power. It's new...we want it NOW!

International Register of Ornamental Plant Cultivars:
Woody Plants: Genera H to M (Winter 2018-2019)

NEW 2.12.2019
Click the link above for 62 pages of new cultivars in the genera Halesia to Myrtus. The first two woody
registers (out of three planned) now cover 114 pages of detailed information and high quality images.
This volume also includes our "New Long Form II" for improved data collection
on recently introduced trees, shrubs, vines, and conifers. This volume is also
available from Amazon Kindle.

International Register of Ornamental Plant Cultivars:
Woody Plants: Genera A to G (Fall 2018)

NEW 10.8.2018
52 pages of new cultivars  from Abelia to Gymnocladus. Use OROC Book 8.1 linked below for other genera. Genera H to N will be updated for Winter 2018. Click link above or image below to download.
This volume is also available fro Google Play Books.

International Register of Ornamental Plant Cultivars:
Hardy Herbaceous Plants (OROC Book 4.2)

NEW 6.9.2018
Click link above for 77 pages of the newest perennials you may want to grow or know about.

Learn more about our free cultivar registration service:
OROC Presentations: PDF - PPTX (Powerpoint)
OROC Main Page: oroc.html


CWP is now available in the new 2021-2022 Edition and the price has remained the same for three years. Click on the logo below for details. Hatch's Perennials renewal will be added in the next few weeks.

HIP is now 100% free online in a larger version. This is the most complete encyclopedia of ornamental  tropical plant, interior landscape plant,  and house plants ever written, including old cultivars, new ones from 2015-2020,  and everything inbetween. Click the logo or here to access. Our new introduction video follows.

Some of our recently revised cultivar counts include:
Acer palmatum=547
Chamaecyparis obtusa=351

New cultivar counts due to revisions and updates:
Hatch's Perennials 2018-2020: new totals: 58 Iberis, 39 Juncus, 185 Opuntia, 65 Origanum, and 108 Nepeta cultivars.

Hatch's Perennials 2017-2018: now 68 Baptisia, 81   Bergenia, 21 Brunnera,362 Campanula, 56 Dicentra, 35 Disporum, 193 Geum, 121 Mentha, 192 Miscanthus, 162 Monarda, 297 Sedum,146 Veronica, and 97 Yucca cultivars. 
  • A few reasons to buy: more cultivars, new cultivars, better and bigger photos, more cultivar-specific data, regular free updates, taxonomist approved, identification tips, academic quality literature references, plant source links, cultivar histories, and portable anywhere on more than 512 known devices
  • Databases - all volumes accessible from a single online or downloadable menu. More than 50% cost savings over buying individual volumes. This option is designed for either a private or public interface.
  • International Coleus Society (ICS)
  • Pauli - free spreadsheet/database to the best 2000 Saintpaulia or African-violet cultivars
  • Looking for Pinetum Novum? This series of conifer files is now included in Hatch's Cultivars of Woody Plants.

    Genus Central is offline and has been replacd by the OROC Registers in tandem with
the Cultivar Encyclopedia

click logo above or here 

Cultivar Name Thesaurus
Lots of adjectives and nouns to help us creatively name
new cultivars 

new cultivars based on particular traits
A summary of our research goals

GPIK: Garden Plant ID Keys
featuring identication keys you can put
on your phone or tablet for in field keying. The
very best keys with the most taxa, newest
nomenclature are almost all digital now

Hundreds of biographical sketches on leading developers of the modern landscape ornamental plants in general, covering botanists who found them, nurserymen who refined and distirbuted them, taxonomists who defined them, plant breeders who improved them, designers and architects who made them art, authors, educators, popular "gurus", noted collectors and other special folk who made our gardens so much better. High-res images of their works are included.
Available at Google Play Books for US$7.20-$9.00

Click underlined title name to view Save copies for your digital library
of distinguished botanical and horticultural monographs and studies

Bean's Trees and Shrubs Hardy in the British Isles
The British master himself and one of the most
influential woody plant guides in history. It
took me 10 years and about $150.00 to
find all the volumes on this shore. Now it's free.
Hibberd's New and Beauitful Leaved Plants
One of the mostly lovely plant books
ever printed. Stunning images and expert
commentary. Hibberd adored variegation.
Wilson's A Monograph of Azaleas
From the collector of many taxa himself,
this is splendid reading for even the
most experienced lover of the genus
Carriere's Trait General des Coniferes
One of the classic, core conifer books of the last two centuries. It's
amazing how many modern popular conifers this man named. Ever
see Carr. after a name? That's him.
Sudworth's Nomenclatural of the Arborescent Flora of the United States
I regard Sudworth as perhaps America's first great woody plant taxonomist. This is a stunning catalog not just of species, their synonyms,
common names, but also numerous cultivated varieties
Bailey's The Nursery Book
This was one of the most widely distributed nursery guides in the US and from the great one himself. I've always liked calling propagation by his terms of seedage, cuttage, and graftage. It seems so proper and academic.Bailey invented the word "cultivar" and conspired to be a "horto-botanical" writer, meaning that both horticulture and botany were blended into the whole. By the way he did all this while Dean of the College of Agriculture at the Ivy League Cornell University.

Virtual Arboretum Resources

Best nursery websites for general ornamentals cultivar info.  

Pauli is a free spreadsheet and database to 2000 of the finest Saintpauliaor African-violet cultivars ever released
and it offers full search functions by flower color, color patterns, petal count, leaf shape, leaf color, breeder, and more. You can add to it and even make it the basis of your
catalog or collection inventory.
 Visit here.

A superb reference source for everything about
garden plant taxonomy, especially nomenclature. This
is an external site but one we very highly recommend.

The Internet Nursery Catalog Archive (INCA) is a massive archive of digitized or saved nursery catalogs from 2000 to present. It is kept by for research purposes and because nearly all the material is subject to copyright, it can be shared online. Portions of it are available on request to researchers with a direct need to material that be offline and especially from closed nurseries and gardens. More than 41% of INCA content is no longer online, making these resources extremely valuable to cultivar, garden, and nursery history researchers. Remembers all those nurseries than went out of business some years back? If they did ornamental cultivar work, we probably have a catalog or ten or portions of new cultivar features.

Since 2005, we decided it made INCA a more versatile, "all purpose" archive for digital research materials and it now includes PDF academic articles, JPG images of new plants, screen captures of important websites, plant identification keys, digitals floras, plant collection lists, garden maps, cultivar registers, plant databases, cultivar release notices, old nursery catalog PDF, horticultural monographs, videos of ornamentals related presentations, scanned articles, and much more. A simple search by genus or species usually produces scores if not a hundred documents which may or may not still be on the web; and now many never were there.

INCA is a major part of our research for cultivar documentation, especially when revising a genus for the Cultivar Encyclopedia. Researchers often send us material to archive for them as we distribute INCA informally to several reliable libraries and partners for safe keeping.

If you have a very specific research project, write us: ornamentals  (at ) and we will list what resources we have. Graduate students, professors, and independent researchers are welcome to contact us. Typically we send a thumbdrive full of files but smaller requests are send by regular email channels.

30+ videos 

Variety Conservation Group (VarCon)
Devoted to propagating, distributing, perserving
documening, and conserving rare and
endangered garden varieties of plants.

Hatch's Cultivars of Woody Plants
2021-2022 Edition

Page Counts (PDF 8 x 10 in. to 8 x 16 in.): 6591

Interface: HTML menu viewable on any internet-connected device. Data files are PDF format.
Megabytes: 1410 (14GB)
Author: Laurence C. Hatch, horticultural taxonomist and cultvar historian with contributions from more than 40 genus experts and users worldwide.
Images: More than 2500 JPG images in digital, high resolution quality. Our standard is a minumum of 1250 pixels wide whenever possible. New images are added monthly.
Cultivar Counts: Abelia=80, Aesculus-=110, Abies=489, Acer palmatum=547, Aucuba-173, Buddleia=318, Cercis=92, Chamaecyparis obtusa=351, Cornus=613, Ginkgo=213, Juniperus=1100+, Loropetalum=67, Lonicera=403, Mahonia=94, Podocarpus=97, Robinia=74, Salix=254, Sciadopitys=94, Taxodium=75, Thuja excluding Platycladus=446, Viburnum-271, plus all genera with cultivars.
Taxa Range: all temperate woody plants including trees, shrubs, conifers, vines, hardy palms, and subshrubs, covering mainly cultivars with occasional botanical taxa added for comparison.Tender woody plants only hardy in USDA zones 8-10 only are covered in Hatch's Interior Plants (HIP).
MIssion Statement: To be and remain the largest  and most complete
catalog of horticultural varieties or cultivars of garden trees, shrubs, vines, and conifers ever published in any medium.
Subscription Duration: You will receive access to all updates through December 31, 2022
Coming soon....Hatch's Perennials 2021-2022 Edition
Our new low price of just $49.00 is a big rollback to encourage more users this year.

Copyright 2019, 2020, 2021.
Laurence C. Hatch.
All Rights Reserved.
No content including images may be used without written permission of the copyright holder. Email us if you need a logo or image for purposes of promoting
a project, encyclopedia, or this site.