Golden Meadow Plant Materials Center 

438 Airport Road 

Galliano, LA 70354 

Avicennia germinans

Black Mangrove
2

Nomenclature

Scientific Name – Avicennia germinans (L.) L.

Common Name – Black Mangrove 

Pre-varietal Source – Pelican germplasm 

Similar Species – Red Mangrove (Rhizophora mangle) and White Mangrove (Luguncularia racemosa) 

Description

Black mangrove is a subtropical woody shrub that 

grows in salt marshes. Mangroves are very hardy, 

having become adapted to harsh environments where 

water and salinity levels fluctuate. Pneumatophores, 

or breather roots, form a network collecting silt and 

debris and controlling erosion. Plant height will vary 

from 4 to 9 feet. Leaves are 1 to 5 inches long, 

elliptical, opposite, thick, leathery, dark green, 

glabrous (smooth) above, and grayish with a tight 

felt-like pubescence beneath. Glands on the 

underside secrete salt. Clusters of small sessile 

flowers with white petals, approximately 1⁄2 inch in 

diameter, are borne on the leaf axils or growing tips 

on the twigs. The fruits are flat, approximately 1 

inch long, dark green and glabrous beneath a velvety 

pericarp. The bark on the black mangrove is thick, 

dark brown or blackish, with rough irregular 

flattened scales. Twigs are grayish in color and 

smooth, with enlargements at the joints. Mangrove 

detritus (dead leaves and twigs) in water feeds 

microorganisms that provide food for young marine 

animals. 

Black mangrove is a unique plant species that, when 

established properly and under applicable conditions, 

has provided land stabilization due to the easy 

transport of seedlings, quick aerial root production, 

underground root systems which increase sediment 

holding capabilities. This plant also provides for 

wildlife and marine habitats. 

Use

Black mangrove is used primarily for wildlife habitat 

along protected shorelines, intertidal salt marshes, 

and marshy barrier islands. Black mangrove is also 

an effective land stabilizer used on interior tidal 

mudflats, dredge-fill, and other artificial sites 

associated with wetland restoration. When 

established on a barrier island, black mangrove 

provides habitat for birds and marine organisms. 

Establishing to protected shorelines, black mangrove 

provides an effective buffer that dissipates low wave 

energies, reduces shoreline erosion, and traps 

suspended sediments and other solids with their 

pneumatophores. Dense stands of mangroves 

produce significant amount of organic matter. The 

cumulative effects of organic matter production, 

sediment trapping, and erosion control not only 

provide shoreline protection but also accelerate 

sediment accumulation. Consequently, black 

mangrove is a sustainable and renewable restoration 

resource, and when properly established, and in the 

appropriate habitat, will persist and potentially 

remain effective indefinitely. 

Black Mangrove

Growth Form and Habitat
3

Habitat

Black mangrove is a woody shrub adapted to 

intertidal salt marsh and marshy barrier islands. It is 

described as a facultative halophyte; that is, it will 

tolerate salt, but salt is not a requirement for its 

growth. The ideal salinity range for establishing and 

growing black mangrove is 25 parts per thousand but 

it can tolerate a wide range of salinities up to 60 parts 

per thousand. Black mangrove can only persist where 

there is adequate protection from wave action. It is 

adapted to sandy, silty clay loam, and muck soils. It 

is sensitive to cold weather, which limits its use to 

the more southerly coastal areas and barrier islands. 

Establishment

Black mangrove can be established successfully from 

container grown plants propagated by seed, 

vegetative cuttings, or air layering. Stands can be 

established by direct seeding on site, but survival has 

generally been poor. The most common method of 

planting black mangrove commercially is by seeds 

germinated and grown in a controlled greenhouse 

environment. 

Black mangrove seeds 

are usually harvested 

from November 

through December. 

Seeds are desiccant 

sensitive and should 

not be allowed to dry 

out. This is referred to 

as recalcitrant seed. 

For best results, plant 

freshly harvested seed. Germination declines in 

relation to duration of storage. Remove the fresh 

pericarp before planting by soaking seed in water up 

to 24 hours. If planting cannot be accomplished soon 

after harvesting seed, place seeds in a wet cool 

environment and plant as soon as possible. 

Black mangrove can be produced in a number of 

container sizes, but trade-gallons (3⁄4 gallon) are the 

most widely used. Trade-gallon containers have a 

higher per unit cost compared to smaller containers 

or direct seeding. A trade-gallon will have one plant 

per container that will grow to an average of 15 to 25 

inches in height. Although black mangrove does not 

produce new plants by underground roots, a welldeveloped root mass is critical to the survival and 

productivity of the transplants. Trade-gallon pots are 

the most commercially available. 

Cone pots are the easiest type of container to grow 

mangroves and transport. The pot will contain one 

plant per container that will grow to an average of 8 

to 12 inches in height. Direct seeding is another 

means of planting but studies show survival has 

generally been poor. 

Planting Date – As a general rule, black mangrove 

seeds can be planted from November 1 to December 

31. Black mangrove plants should be transplanted in 

early spring. Some additional considerations include 

the following: 

3⁄4 Black mangrove seeds are desiccant sensitive 

and should not be allowed to dry out. 

3⁄4 Seeds should be soaked in water up to 24 

hours to remove the fleshy pericarp. If 

planting is delayed, seeds should be floated in 

water (fresh or saline) with seed no greater 

than 3 inches thick. 

3⁄4 Plants should be grown in protected 

environment (e.g. greenhouse, etc.) with 

climate controlled temperature to keep cold 

temperatures and frost off of plants. 

3⁄4 Black mangrove plants can be transplanted 

anytime past last frost date. 

Planting Location – It is critically important to 

remember that black mangrove is cold sensitive and 

must be planted in areas where it does not readily 

freeze. Black mangrove can be used for erosion 

control along protected shorelines and is an effective 

soil stabilizer when used on marshy barrier islands, 

interior tidal mudflats, dredge-fill sites, and other 

areas of loose and unconsolidated soils associated 

with marsh restoration. Also, black mangrove can be 

used for wildlife and marine habitat. 

Protected Shoreline Plantings – Protected shoreline 

plantings are typically planted as a single row 

parallel to the shoreline. Transplants should be 

planted at mid-point between the high and low tide 

elevations. Plant spacing within the row will vary 

Pericarp

Recalcitrant seed 
4

according to the size of the transplant materials being 

used and the rate at which full coverage is desired. 

Trade-gallons generally are planted on 5 to 8 foot 

centers and cone pots on 2 to 5 foot centers. Under 

desirable site conditions, black mangrove will spread 

by dropping seed, filling spaces between plants and 

nearby areas, and will grow to its highest and lowest 

elevation. It is not uncommon for black mangrove to 

establish itself in other areas where seeds may have 

floated in. 

Interior Plantings – In addition to planting 

protected shorelines, black mangrove can be planted 

on mudflats and dredge-fill sites. The planting 

configuration should be designed to provide 

maximum coverage. Planting large areas generally 

will require a significantly large number of plants. 

Where applicable, cone pots 

can be used and placed in a 

row-column configuration. 

The row and plant spacing 

can vary from a few feet to 

many, depending on the 

objective of the planting, the 

target rate for coverage, and 

available resources. Direct 

seeding can also be done by 

flying it over with a plane or 

broadcasting it over the 

desired area. However, this method is not readily 

used because plant survival has generally been poor. 

Marshy Barrier Islands – Marshy barrier island 

planting are typically planted for wildlife and marine 

habitat. Although plant configuration may vary, 

typically it is planted similar to interior plantings. 

Planting Methods – When planting trade-gallons 

place transplants in a dug hole. Post-hole diggers, 

gas drills with modified bits, or any other method of 

digging are satisfactory. The planting hole should be 

the same size or only slightly larger than the root ball 

and only deep enough so that the top of the root ball 

is flush or slightly below ground. The top of the root 

ball should not protrude above, nor be more than 2 

inches below, normal ground. The planting hole 

should be tightly sealed around the plant to prevent 

the plant from wobbling and to close air pockets 

around roots. Plants should remain erect after 

planting. 

Planting sites where plants may have a tendency to 

wash out may require the addition of a plant anchor. 

A plant anchor consists of 1⁄4 inch mild steel re-bar 

bent into a crosier hook (candy-cane shape) and 

pushed down into the soil so that the hook lies across 

the root ball pinning it to the ground. Anchors are 

generally about 30 inches in overall length and will 

add to the cost of the planting. However, anchors are 

generally necessary at unusually problematic sites to 

prevent plants from washing out. 

When planting cone pots, place transplants in a dug 

hole. Dibbles bars, gas drills with modified bits, or 

any other method of making a small hole in the 

ground is satisfactory. The planting hole should be 

the same size or slightly larger than the top of the 

root ball and only deep enough so that the top of the 

root ball should not protrude above nor be more than 

2 inches below normal ground. The planting hole 

should be tightly closed around the plant to prevent 

the plant from wobbling and to close air pockets 

around roots. Plants should remain erect after 

planting. Typical plant anchors are not usually used 

on cone pots because they are usually too large in 

relation to the plant and may cause damage to the 

plant. 

Fertilization – There is no clear consensus on the 

effectiveness of fertilizer when used in saturated 

and/or anaerobic soils. However, the additional cost 

of fertilizer is a small investment given the overall 

cost involved in vegetative restoration. High 

nitrogen slow-release fertilizer tablets will add 

approximately .08 to .10 cents to the cost of an 

individual plant. 

Slow-release fertilizer tablets are commercially 

available in a range of weights and analyses. 

Shoreline Protection

Interior Marsh Planting
5

Recommended tablet weight should be between 15 to 

25 grams and have a nitrogen content of not less than 

15% or more than 30%. When using tablets with 

trade-gallon plants, push the tablet into the top 3 

inches of the root ball immediately before or 

immediately after planting the transplant. The 

resulting hole should be pinched closed. When using 

tablets with cone pots, set the plant and then place 

the tablet either along side or on top of root ball. 

Plant Materials Source – Plant materials are 

generally obtained from two sources, a donor 

wetland site or commercial nurseries. The use of 

donor plant materials from a wetland site is not 

recommended because young plants will affect the 

health and vigor of the donor stand or community 

and plant mortality is generally high. Best results are 

collecting and using seed. In addition, the removal 

of plant materials without the applicable permits may 

be in violation of state and federal regulations. 

Removing plant materials from donor stands is not 

typically recommended. 

Nursery-grown stock is generally the most reliable 

and ecologically appropriate way to obtain plant 

materials. A number of commercial nurseries 

produce and maintain black mangrove transplants. 

Trade-gallon and cone pots are the two most 

common sizes, but most nurseries will contract for 

other container sizes. 

Vegetative specifications should be used to tailor 

plant material quality and quantity to a specific 

project. These specifications should include 

acceptable sources, cultivars, ecotypes, plant size, 

and height, container specifications, and extent of 

root development. In addition, other requirements 

such as climatic hardening are commonly included. 

A list of commercial wetland plant nurseries and 

assistance in developing plant material specifications 

is available from the Natural Resources Conservation 

Service. 

Other Considerations – There are a number of other site-specific elements that should be considered 

when working with black mangrove. These conditions represent extremes and should be thoroughly 

investigated before committing to a significant project if any of these conditions occur. 

3⁄4 Soil load-bearing properties – It is not uncommon for soils (especially in dredge deposit sites) to be 

fluid to the point that they physically will not support the weight of plants. This is an indicator of soils 

with a very high water-to-mineral ratio. 

3⁄4 Shoreline configuration – Abrupt and steep cut-banks are indications of high wave energy and/or 

highly erodible soils. Special precautions may be required to keep transplants from dislodging before 

becoming established. 

3⁄4 Smothering – Precautions should be taken when planting in areas of heavy floating debris. Both 

mechanical damage to the plants from surf trash and smothering from other plants are common 

detriments to black mangrove. 

If any of these conditions are present, consult with a wetland specialist for additional information 

and/or possible alternatives. 

 

February 2005 

For Additional Information 

Golden Meadow Plant Materials Center 

438 Airport Road 

Galliano, LA 70354 

Phone: (985) 475-5280 

Fax: (985) 475-6545 

Web: http://Plant-Materials.nrcs.usda.gov

Email: gary.fine@la.usda.gov
6

For more information about this and other plants, please contact your local NRCS field office or Conservation District, and visit the PLANTS Web 

site<http://plants.usda.gov> or the Plant Materials Program Web site <http://Plant-Materials.nrcs.usda.gov> 

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alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center at 202-720-2600 (voice 

and TDD). 

To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, Room 326W, Whitten Building, 14th and Independence Avenue, SW, 

Washington, DC 20250-9410 or call (202) 720-5964 (voice or TDD). USDA is an equal opportunity provider and employer