Welcome to the world of Cold Hardy Palms. If you live in USDA Zone 6b or above, you can grow palms. Not just any palms mind you, but native palms too - Especially native palms!

The world of cold hardy palms is curious. Knowledgeable gardeners, nurserymen, and horticultural agents have known about cold hardy palms for decades, but the knowledge somehow hasn’t hit the streets. Finally, however, the time of cold hardy palms has come to the limelight, principally because of the Internet and its world-wide-web.

I present to you an introduction to the cold hardy palms. Hardiness is to cold snaps, not extended freezes, (which is why USDA Zone 6b is about the limit).

Dwarf Palmetto (Sabal minor), the world’s cold-hardiest dwarf palm. Jaycee Park, Raleigh, NC.

Figure 1. USDA Climate Zones______

USDA Winter Lowest Temp. (Avg.)_

ZONE __Fahrenheit_ ___Celsius___

5a -20 to -15 -29 to -26

5b -15 to -10 -26 to -23

6a -10 to -5 -23 to -21

6b -5 to 0 -21 to -18

7a 0 to 5 -18 to -15

7b 5 to 10 -15 to -12

8a 10 to 15 -12 to -9

8b 15 to 20 -9 to -7

9a 20 to 25 -7 to -4

9b 25 to 30 -4 to -1

10a 30 to 35 -1 to 2

10b 35 to 40 2 to 4

11a 40 to 45 4 to 7

11b______45 to 50_______7 to 10___

List of Cold Hardy Palms

USDA Zones 6b to 8a.

* Expect leaf damage from average low in listed zone; ** could be lethal.

List is cumulative upwards.

6b (-5 to 0 F) (-21 to –18 C)

Rhapidophyllum hystrix
Sabal minor

7a (0 to 5 F) (-18 to –15 C)

Sabal 'Birmingham'
Sabal 'Louisiana'

Sabal ‘Tamaulipas’

7b (5 to 10 F) (-15 to –12 C)

Sabal ‘Brazoria’*

Sabal uresana
Trachycarpus 'Bulgaria'
Trachycarpus fortunei
Trachycarpus nanus
Trachycarpus takil
Trachycarpus wagnerianus

8a (10 to 15 F) (-12 to –9 C)

Brahea armata*
Brahea berlandieri aka B. bella
Brahea decumbens*

Brahea dulcis*
Brahea moorei*
Butia capitata*

Butia eriospatha

Butia capitata odorata

Butia paraguayensis*

Butia purpurascens*
Butia yatay*
Chamaedorea microspadix*

Chamaedorea radicalis*

Chamaerops humilis*

Chamaerops humilis cerifera*
Jubea chilensis**
Nannorrhops ritchiana**

Nannorrhops ritchiana ‘Silver’**

Phoenix dactylifera**

Phoenix loureiroi humilis**

Phoenix loureiroi pedunculata**

Phoenix sylvestris**

Phoenix theoprastii**
Sabal domingensis*
Sabal etonia

Sabal maritima*

Sabal mexicana*
Sabal palmetto

Sabal rosei*

Serenoa repens

Trachycarpus latisectus*

Trachycarpus ‘manipur’

Trachycarpus martianus*

Trachycarpus ‘Naga Hills’

Trachycarpus oreophilus*

Trachycarpus princeps*

Trithrinax brasiliensis*

Trithrinax campestris*

Washingtonia filifera**
Washingtonia filifera-x-robusta**

Washingtonia robusta**

Figure 2. Average Frost Dates USA

Zone Last First

Z6b April 30 Oct 18

Z7a April 25 Oct 20

Z7b April 10 Oct 25

Z8a March 30 Nov 1

Z8b March 15 Nov 15

NOTE: Whether it is grass, perennials, annuals, trees or palms you are planting, you have to meet the requirements of the plant to succeed. That means: proper site selection; site and soil preparation; adequate irrigation; selection of the right plant and right size of plant; and planting at the optimal time.

That being said, nature is not perfect. Poor health, diseases, pests, natural disasters, and old age befall people and palms alike. Nothing lasts forever. Palms are not a panacea. They are simply a choice that you may not have known about, a treasure that you have been deprived of, and a new hope.

No guarantee is made, given, or implied. Please understand.

Chamaerops humilis, Manteo, North Carolina

Acknowledgements

What is contained herein was gleaned from the tree of knowledge grown and cared for by many others. This book is a simple documentary of that lovely tree.

If you enjoy this book you can thank my wife and friends for their encouragement and support. They deserve it. If you don’t like this book you’ll blame me. I rather hope that you like it.

For some twenty years Gary Hollar of New Bern, North Carolina has grown cold hardy palms and sold them to an increasing assemblage of palm smitten gardeners. I never would have discovered cold hardy palms if not for Tony Avent of Raleigh, with his outrageous and mesmerizing catalogs from Plant Delights Nursery. Tony has opened the doors of the world to palms - and so much more! The same is true for Carl Schoenfeld and Wade Roitsch of Yucca Do Nursery and John Fairey of Peckerwood Gardens, both in Hempstead, Texas. We would be ever so much poorer without their efforts. It is impossible to ignore the assiduous work of Martin Gibbons, Tobias Spanner, Nigel Kembrey, Kiril Donov and their friends overseas. My hat is off to you.

Scott Zona has published his studies of the genus Sabal. Thank you Mr. Zona.

Lacepede was right. “It takes centuries to nurture the tree of knowledge and to make it grow, but one crushing blow from the axe of destruction chops it down.”

Let us not chop it down.

The Palm And Cycad Society Of Australia (PACSOA) must be thanked for nurturing the tree. They have kindly made this book available for free on their website (www.pacsoa.org.au). Thank you Mike Gray.

This book is free to download, free to copy, free to distribute, and free to translate – just give me credit as author next to your credit as translator. Why free? Sunshine is free. Rain is free. The air we breathe is free. Why not a book!

Special thanks to Robert Craddock for editorial insights at a dark hour - mostly before and after his long day’s work.

Key to Cold Hardy Palms[1]

USDA Zones 6b-8a

1A Trunk absent or creeping or below

ground (not upright)……go to….…2

1B Trunk upright, even if low and

squat……………………go to…....9

Non-trunk or Subterranean trunk

2A No sharp teeth on petioles…...……3

2B Sharp teeth on petioles……………4

3A Inflorescence terminal (at end and

center of stem), upright, extends

beyond leaves

- Nannorrhops ritchiana Z8b

3B Inflorescence not terminal….….….4

4A Hastula truly palmate; petioles

armed……… ………………….…5

4B Hastula costapalmate or strongly

costapalmate; petioles not armed…7

5A Inflorescence extends well beyond

leaves; back of leaves white, front of

leaves green - Brahea moorei Z8a

5B Inflorescence held within leaves….6

6A Leaves very white front and back;

leaves large (30-36inches across);

- Brahea decumbens Z8a; or

6B Leaves green, blue-green, or silvery;

leaves small (20-24inches across)

- Serenoa repens Z8a

7A Inflorescence bushy and < leaves;

hastula costapalmate & often

highly skewed - Sabal etonia Z8a

7B Inflorescence sparse and > leaf

length; hastula costapalmate……..8

8A Seed (not fruit) 4-7mm; hastulas

moderately skewed. - Sabal minor

Z7a-6b

8B Seed (not fruit) large 10-13mm;

hastulas often extremely skewed;

- Sabal ‘Tamaulipas’ Z7a

Palms with a trunk

9A Leaves pinnate (like fern leaf or

ostrich feather)……go to………..10

9B Leaves palmate or costapalmate…14

10A Thick sturdy trunk, even massive

(not thin and narrow)……………11

10B Thin trunk (very short or up to

several feet)…………..………..13

11A Deep-green glossy leaves (with

wide leaf pinnae); pinnae near leaf

base not modified into spines; very

stout trunk - Jubea chilensis Z8b

11B Leaves gray-green to green,

pinnae long and thin…………..12

12A Petioles toothed; basal pinnae not

modified into spines; Butia sp.Z8a

12B Basal pinnae modified into spines

- Phoenix sp. Z8b

13A Short, 6-inch trunk at most; red

berries

-Chamaedorea radicalis Z8b, 8a

13B Tall narrow trunk , red berries

-Chamaedorea microspadix Z8b, 8a

14A Wide, squat, trunk has long, sharp,

conspicuous spines; leaves palmate

– Rhapidophyllum hystrix Z7a, 6b

14B Trunk lacks spines (but leaves may

have teeth)……………………...15

15A Leaf stem bears sharp teeth...…..16

15B Leaf stem w/o sharp teeth……....21

16A Teeth small, trunk average……..17

16B Teeth very large, trunk wide...…20

17A Hastula palmate:

Loosely clustering leaning trunks

- Serenoa repens Z8a; or

Tightly clustering upright trunks

-Chamaerops humilis Z8a

17B Hastula costapalmate; petioles

armed…………………….……..18

18A Inflorescence >>leaves, hangs

gracefully down 6-ft or more

– Brahea armata Z9a, 8b

18B Inflorescence not as above…….19

19A Dead leaves naturally fall off trunk,

boot and all, leaving a clean trunk

- Brahea edulis Z9a, 8b

19B Dead leaves remain atached to

trunk for some time

- Brahea dulcis/ B. berlandieri Z8a

20A Abundant leaf filaments

-Washingtonia filifera Z8b, 8a

20B Few leaf filaments

- Washingtonia robusta Z9a, 8b

21A Inflorescence terminal (at end and

center of trunk), upright, and much

longer than leaf-length

– Nannorrhops ritchiana Z8a

21B Inflorescence not terminal……...22

22A Leaves truly palmate; Abundant,

course hair surrounds trunk at leaf

bases (although trunk may be bare

further down) – Trachycarpus sp.

22B Leaves costapalmate (or weakly so)

Trunk not hairy…………………23

23A Trunk 20-24inches wide, not

tapering markedly; inflorescence

longer than leaves; fruit 12-14mm

wide; seed 8-10mm wide.

Sabal domingoensis Z8b.

23B Not as above…...…go to………..24

24A Leaf weakly costapalmate; pinnae

divided < 2/3 leaf length…..…...25

24B Leaf very costapalmate; pinnae

divided > 2/3 leaf length……….26

25A Trunk normal - Brahea nitida Z9a

25B Trunk short & squat except very

old specimens where boots have

fallen off; Seed (not fruit) 4-7mm

-Sabal ‘Louisiana’ Z7a

26A Leaves glaucus; Pinnae very long

at ends; inflorescence > leaves;

Seed (not fruit) 10-14mm)

– Sabal uresana Z8a, 7b

26B Leaves green or greenish…..…..27

27A Pinnae divided > 3/4 leaf length,

ends long, wispy…………..…...29

27B Pinnae divided < 3/4 leaf length;

pinnae broad …………………...28

28A Seed (not fruit) 8-13mm;

Inflorescence = leaves

– Sabal mexicana Z8b, 8a

28B Inflores. > leaf - S. ‘Brazoria’ Z7b

29A Inflorescence = leaf; seed 5-9mm;

– S. palmetto Z8a

29B Inflorescence < leaves; trunk

slow – Sabal ‘Birmingham’ Z7a

Trachycarpus fortunei Taylor Form, Pullen Park

Trachycarpus fortunei, Pullen Park, Raleigh, NC

Palm Morphology

Boot: The leaf-base attachment to the trunk. Some palms shed the boot with the leaf. Some retain the boot for long periods, only shedding the oldest ones.

Costapalmate: A leaf where the hastula is elongate and pointy.

Hastula: Found in palmate and costapalmate leaves. The upper leaf-end of the stem where the leaf and pinnae are attached (do not confuse with rachis!).

Inflorescence: The branched stem that bears the palm flowers, and later its fruit. May be sparse - having a few short branchlets at long intervals, or bushy – having a congestion of branchlets.

Palmate: A leaf where the hastula is round or ovoid, not elongate and not extending along the leaf midrib; Hastula resembles an arm that ends in a fist.

Petiole: The woody extension that attaches the leaf to the trunk.

Pinnae: Divisions of the leaf found along the midrib in pinnate leaves or as spread fingers in palmate and costapalmate leaves.

Pinnate: The leaf stem continues as the midrib and pinnae are attached to the midrib like filaments of a feather to the feather shaft. Leaf resembles a fern or cicad leaf (see Butia & Phoenix palms)

Rachis: The lower part of the stem that extends along the underside of the leaf along its midrib (Not to be confused with the hastula!).

Trunk: The aerial or underground body that bears the leaves. When visible above ground (aerial), the palm is said to have a trunk.

Very Costapalmate: Hastula resembles a praying hand with a long middle finger.

Palmate hastula.

Costapalmate hastula.

Very costapalmate hastula.

Rachis on a very costapalmate leaf.