# Clusterspike Indigobush (Amorpha herbacea) > A low indigobush of southern sandhills whose clustered white to violet flower spikes feed native bees in early summer. Also called clusterspike false indigo. Category: Native Shrubs. Grown from seed by Blue Whale Trees. Web version: https://bluewhaletrees.com/plants/clusterspike-indigobush/ ![Clusterspike indigobush (Amorpha herbacea) white flower spikes with orange anthers among small leaflets](https://bluewhaletrees.com/img/plants/clusterspike-indigobush-h1610-800.jpg) *Photo: David J. Stang, CC BY-SA 4.0 ยท [Wikimedia Commons](https://commons.wikimedia.org/wiki/File%3AAmorpha_herbacea_1zz.jpg)* ## Facts - Type: Shrub - Mature height: 2 to 4 ft - USDA hardiness zones: 7 to 10 - Grows wild in: Sandy barrens and dry uplands - Native range: Alabama, Florida, Georgia, North Carolina and South Carolina - Sun: Full, Part - Soil moisture: Dry, Average - Growth rate: Slow - Traits: Showy flowers, Wildlife value, Drought tolerant, Nitrogen fixing - Sold as: Saplings, Seed Heights and zones are typical ranges for the species in cultivation; local conditions and seed source shift them. ## Availability Not yet priced online. Ask at captain@bluewhaletrees.com or leave an email on the web page to be told when it is listed. ## Notes Clusterspike indigobush is a low shrub of dry sandhills, scrub and open pine woods on the Coastal Plain from North Carolina into Florida. It grows from a thick, woody rootstock that can run about 6 feet through the sand. Its name comes from the several flower spikes clustered at the top of each stem. One variety, found only in the pine rocklands around Miami, is listed as endangered by Florida and under the federal Endangered Species Act. Grow it in a sunny, sandy bed or a dry meadow, where bees and butterflies find its early summer bloom. ## Size, growth and what to expect No source rates its growth, so our growth estimator treats it as a slow grower, like our leadplant, about a foot a year. It makes a shrub 2 to 4 feet tall and 3 to 4 feet wide, and a few reach 5 feet. Its gray, downy leaves carry up to 45 small leaflets, and the foliage has a faint smell of cat urine. Four to twelve slender spikes, each 4 to 7 inches long, cluster at the top of the stems from May into July. The small flowers range from white to blue violet, with yellow to orange anthers. Like other amorphas, it bears tiny pods with a single seed each, which ripen brown in mid to late summer. It grows wild on the Coastal Plain from North Carolina to Florida and west into Alabama, and now and then in the Piedmont. Its home is dry, open woods, sandhills, scrub and savannas. It is the most widespread of the low indigobushes of the Southeast. ## How to grow Clusterspike Indigobush Clusterspike indigobush wants full sun or light shade and a sandy soil that drains well. Once rooted it takes long dry spells, but not standing water or salt spray. Set plants 3 feet apart and 2 feet from a wall. At its size it can go within 15 feet of overhead wires. Saplings ship bare-root or potted. Plant them dormant, in a hole wider than the roots and no deeper. Set the crown at the soil line, put the native soil back in, and keep the mulch thin and clear of the stems. Seed sprouts best when it is rubbed out of its pod first. Sow it about a quarter inch deep in spring. Cleaned seed keeps well in the freezer. Water weekly through the first summer, then only in long droughts. Heavy shade stunts it, so keep taller plants from closing over it. Each flower carries both male and female parts. A lone plant sets some seed with its own pollen and more with pollen from another plant, so plant two or more seedlings from different parents. Native bees work the flowers, and it feeds the caterpillars of the silver-spotted skipper and the southern dogface. ## Sources - [Wilbur 1975, A revision of the North American genus Amorpha (Leguminosae-Psoraleae), Rhodora 77(811): 337-409, species 3 on pages 352-357](https://archive.org/details/biostor-138235) - [Lady Bird Johnson Wildflower Center: Amorpha herbacea, Clusterspike False Indigo, Cluster-spike Indigobush](https://www.wildflower.org/plants/result.php?id_plant=AMHE) - [Florida Native Plant Society: Amorpha herbacea, cluster-spike indigo-bush](https://www.fnps.org/plant/amorpha-herbacea) - [Georgia Department of Natural Resources, Georgia Biodiversity Portal: Amorpha herbacea var. floridana, Florida Leadbush](https://georgiabiodiversity.org/portal/profile?group=plants&es_id=15495) - [Linares and Koptur 2010, Floral biology and breeding system of the crenulate leadplant, Amorpha herbacea var. crenulata, an endangered South Florida pine rockland endemic, Natural Areas Journal 30(2)](https://doi.org/10.3375/043.030.0202) - [Roncal and others 2006, Propagation protocol for the endangered crenulate lead plant, Amorpha herbacea var. crenulata, Native Plants Journal 7(1): 89-93](https://doi.org/10.2979/NPJ.2006.7.1.89) - [Marchin and others 2009, Are rare species less shade tolerant than common species in fire-prone environments? A test with seven Amorpha (Fabaceae) species, Plant Ecology](https://doi.org/10.1007/s11258-009-9614-3) - [NatureServe Explorer: Amorpha herbacea, Cluster-spike Indigobush](https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.138999/Amorpha_herbacea) - [Florida Natural Areas Inventory: Tracking List](https://www.fnai.org/PDFs/tracking/element_tracking_summary_current.pdf) - [U.S. Fish and Wildlife Service, ECOS: Crenulate lead-plant, Amorpha crenulata](https://ecos.fws.gov/ecp/species/6470) - [USDA NRCS PLANTS Database: Amorpha herbacea, AMHE](https://plants.usda.gov/plant-profile/AMHE) - [GBIF occurrence search, preserved specimens of Amorpha herbacea in the United States](https://www.gbif.org/occurrence/search?taxon_key=5357397&country=US&basis_of_record=PRESERVED_SPECIMEN) - [USDA Forest Service, Woody Plant Seed Manual (2008), Amorpha chapter](https://www.fs.usda.gov/nsl/Wpsm/Amorpha.pdf) ## Read before planting - [Ten planting mistakes that quietly kill trees](https://bluewhaletrees.com/articles/ten-planting-mistakes/index.html.md) - [Transplanting young trees: timing, water and protection](https://bluewhaletrees.com/articles/transplanting-young-trees/index.html.md) - [Protecting young trees from voles, rabbits, deer and squirrels](https://bluewhaletrees.com/articles/protecting-trees-from-animals/index.html.md) - [The habitat around a tree is part of the tree](https://bluewhaletrees.com/articles/habitat-around-a-tree/index.html.md) - [Invasive vines and shrubs are what is killing your woods](https://bluewhaletrees.com/articles/invasive-vines-and-shrubs/index.html.md) - [Native trees and shrubs for butterflies and moths: host plants first, nectar second](https://bluewhaletrees.com/articles/native-trees-for-butterflies-and-moths/index.html.md) ## Related - [Planting-site check](https://bluewhaletrees.com/tools/site-check/index.html.md): for a thrive, struggle or fail verdict on Clusterspike Indigobush, add ?species=clusterspike-indigobush with zone (2 to 10), sun (full, part, shade) and moisture (dry, average, wet) to that address, for example ?species=clusterspike-indigobush&zone=7&sun=part&moisture=average. - [Companion species for Clusterspike Indigobush](https://bluewhaletrees.com/tools/companions/index.html.md?species=clusterspike-indigobush): the natives that share its ground and the plants that pair with it in a yard. - [Growth estimator](https://bluewhaletrees.com/tools/growth/index.html.md): how the height and trunk projections are made; the estimate itself runs in the browser at https://bluewhaletrees.com/tools/growth/#species=clusterspike-indigobush - [Seed sowing planner](https://bluewhaletrees.com/tools/sowing/index.html.md): how Clusterspike Indigobush is sown, in the chart for every species (treatment, cold days, depth, timing); the dated plan runs in the browser at https://bluewhaletrees.com/tools/sowing/#species=clusterspike-indigobush - [Pollination planner](https://bluewhaletrees.com/tools/pollination/index.html.md): what Clusterspike Indigobush needs for a crop and how many to plant, in the table for every species; the planner runs in the browser at https://bluewhaletrees.com/tools/pollination/#plants=clusterspike-indigobush:2 - [Bloom and fruit calendar](https://bluewhaletrees.com/tools/calendar/index.html.md): the months Clusterspike Indigobush flowers and fruits, in the grid for every species.