Rhododendron Growing

Some of the parent plants from the 2024 ARHS Seed Exchange

Seed Parent_24

Atlantic Rhododendron & Horticultural Society
Check here for more information on Rhododendrons and Azaleas

The ARHS 2024 Seed Exchange List is now open to members.
An Introduction with updates on the Exchange is included.
Orders should be submitted using the Order Form provided.
Orders from ARHS members will be processed on a first come, first served, basis until Feb.2, 2024
Orders from the world at large will be welcome until the end date of April 30, 2024
The list will be updated periodically to indicate availability
Enquiries may be sent tosbryson@ns.sympatico.ca

Archived ARHS Seed Exchange Lists

2009	2010	2011	2012	2013
2014	2015	2016	2017	2018
2019	2020	2021	2022	2023

Growing Rhododendrons and Azaleas from Seed

growing

You may access the Power Point file via this link and download or view online.
This was originally presented at an ARHS meeting by S. Bryson and Bill Wilgenhof

Below is the link to an article written for The ARS Journal a few years ago.
The information is essentially the same, although there have been some minor changes in medium.
'How to Grow Rhododendrons from Seed'

More Pics of Seedling Growth

Below are some pictures of Bill's set-up for growing Rhododendrons and Azaleas under lights over the winter

This is rather a poor photo showing one growing chamber with fluorescent lights and trays of rhododendron seedlings, now about 4 months of age. There are two chambers such as this ; able to accommodate in excess of 1600 seedlings.	These seedlings are about 4 months of age and are growing in 6-cell packs. Most plants can quite happily stay in this size pack until outdoor transplant time in June.They are starting to show some "personality" by this stage of growth. Those in the 'know' can identify qualities that may have been contributed by one or both parents. The yellow sticky boards are to trap any stray fungus knats that may appear...they seem to like the nice moist soil in the rhododendron packs. Bill is convinced that the 'best' seedlings at this stage will likely be the 'best' once they are growing outside.
	These seedlings, from 1999 Seed Exchange, are about 8 months of age. They spend the first summer under 50% shade cloth. It is removed at summer's end. Some winter wind protection is provided by a wooden baffle around the nursey bed.They actually were completely buried in snow during the winter of 2000-2001.They came through the first winter very well. The image below shows a portion of this bed in late summer/fall 2001
This seedling bloomed for the first time in 2000. It has been tentatively named "Sproeten" Barbara Cook X Janet Blair (ARS #765/1992) We have sent cuttings of this plant for propagation via VanVeen Nursery and the ARHS. Returning plants were made available to ARHS members, so a few should have her growing successfully in their gardens. We received two plants and they bloomed in 2010. Seed supplied by P.Walton, ARS member from New Jersey
"Sproeten" blooms beautifully most years. There have been some years 'she' suffered some bud damage. Both the blooms and the plant are very nice. Bloom 2005 In 2005 we discovered a 'sister' plant which bloomed about 10 days later. Despite being in a very crowded situation it was lovely. We have dubbed it "Ruby Lemon", as an alternative to being called "Sproeten sibling" #5. This plant was also propagated from cuttings and some "returned" in 2009.
This plant is another sibling to "Sproeten" Winter has taken out the top quarter of the plant. We hope the remains are okay!	Barbara Cook X Janet Blair (ARS 1992 # 765)
ARS95#644 'Calsap' x pachysanthum Several plants in the group. All very early bloomers with "pachysanthum" type foliage and 'Calsap' blotch	Rhododendron seedling AR'96(Alstrup)#61...a pale mauve fading to white with a very dark purple blotch. There are several siblings of this plant which bloomed in 2002-03

Below we have some examples of plants grown from ARS1992 #608, from a cross made by Shirley and Alan Anderson of New Jersey. We have quite a number of sister plants, many are yellow, but a couple are more ivory plus one that is pink. We have had several of these propagated, so we have a few extra copies. Most bloomed in 2010.

This yellow Rhododendron is one of several from a complex cross (ARS92#608) As of spring 2003 there about 13 sibling plants	ARS92#608 sibling dubbed "Ivory Cloud"
An ivory sibling (ARS92#608) with a slight blotch	Some years it comes across as quite yellow
ARS92#608 sibling, the search for yellow gives pink	This plant has grown to be very wide