Haemanthus and Scadoxus Culture

jonathanhutchinson@rhs.org.uk jonathanhutchinson@rhs.org.uk
Mon, 28 Jun 2010 04:48:52 PDT
The correct spelling for the Scadoxus multiflorus subspecies is actually katharinea, named after Katharine Saunders .... Not a lot of people know that.

-----Original Message-----
From: pbs-bounces@lists.ibiblio.org [mailto:pbs-bounces@lists.ibiblio.org] On Behalf Of J.E. Shields
Sent: 27 June 2010 19:46
To: Pacific Bulb Society
Subject: [pbs] Haemanthus and Scadoxus Culture

I'll post some notes on these two genera here in response to an inquiry.


Most Haemanthus seem to be winter-growing, especially those native to the 
Western Cape and Northern Cape provinces in South Africa.  These include 
the following:


Others are summer-growing.  They are found in eastern South Africa, from 
Mpumalanga to KwaZulu-Natal and the Eastern Cape provinces.  These are:

humilis humilis
humilis hirsutus

When the bulb is dormant, keep it absolutely dry.  The winter-growing bulbs 
stay in the greenhouse all summer long, with no water.  We do move the pots 
to beneath the benches, and the glass is painted with a heavy coat of 
shading compound.  The exhaust fan runs most of the time, controlled by a 
thermostat set at around 80 F (ca. 27 C).  The greenhouse air is often as 
hot as 125 F (52 C) on sunny summer afternoons.  Mature bulbs seem to 
tolerate this.

The summer-growing bulbs spend the winter in that greenhouse and the summer 
outdoors in full sun (and rain).  In winter, that same greenhouse may get 
as cold as 33 or 34 F (+01 C) at night.  They spend the winters dry in that 

Finally, a few species, mainly from the Drakensberg, are evergreen and may 
need some water off and on all year long:


H. albiflos and H. pauculifolius grow like weeds, but H. deformis barely 
struggles along under my care.

When you grow Haemanthus from seed, try to keep the young seedlings growing 
continuously for the first two years.  This means they have to be in a mild 
(68-75 F or 20-23 C) environment with long daylight (fluorescent lights on 
timers for 16 hrs on/8 hrs off) for the entire time.  Keep them well 
watered and well fertilized.  Finally at 18 to 24 months of age, when their 
parent-bulb growing season is starting, move them into the greenhouse  and 
put them on their normal winter- or summer-growth schedule.


I only have experience with Scadoxus multiflorus katherinae, S. 
membranaceus, and S. puniceus.  All three are summer-growing and, under my 
conditions, deciduous in winter.  All three go outdoors in Spring (May, 
here) after all danger of frost is past and stay there till September 
(early autumn).

S. puniceus is by far the easiest to grow.  It blooms in February, just 
before the new leaves appear.

S, membranaceus and multiflorus katherinae bloom less reliably for me; I 
have the feeling they would do better if they were grown evergreen, but my 
greenhouse conditions do not seem to allow that.

I hope this is of some help to enthusiasts of Haemanthus and Scadoxus.

Jim Shields
in hot and humid central Indiana

Note: I have most of but not all of the Haemanthus species I listed, so 
there is a little extrapolation involved in my comments.

Jim Shields             USDA Zone 5             Shields Gardens, Ltd.
P.O. Box 92              WWW:    http://www.shieldsgardens.com/
Westfield, Indiana 46074, USA
Tel. ++1-317-867-3344     or      toll-free 1-866-449-3344 in USA

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