by Deborah Birge – Fort Bend County Master Gardener

Ground orchids can make a shade garden feel special: they offer pleated foliage, upright flower spikes, and the satisfaction of growing something that gives your garden a tropical look. But not all ground orchids behave the same way. Bletilla striata, commonly called Chinese ground orchid or hardy orchid, is widely grown as a manageable perrenial. Eulophia graminea, often called Chinese crown orchid, is a very different case: in Florida and other warm regions, it has become an invasive plant of concern because it spreads readily.  Phaius tankervilliae, commonly called nun’s orchid, falls between those two in garden decision-making: it is a beautiful, large terrestrial orchid that is frost sensitive. But for areas with no annual frost, it has been reported as invasive, including Hawaii and Jamaica.

The key takeaway is simple: Bletilla striata is generally the safest ornamental choice in suitable climates, Eulophia graminea should be treated with caution and avoided where it is naturalizing, and Phaius tankervilliae is best approached as a region-dependent, large tropical ground orchid rather than an automatic landscape plant.

Bletilla striata: The Behaved Hardy Ground Orchid

Bletilla striata is the plant most gardeners mean when they talk about a hardy ground orchid. It grows from pseudobulbs and sends up pleated, sword-shaped leaves in spring. The flowers are usually pinkish purple, though white and other cultivated forms are available. The flower spikes rise above the foliage and bloom in late spring to early summer, giving the plant an orchid look without the orchid fussiness.

In the garden, Bletilla striata prefers organically rich, moist but well-drained soil and part shade. In our area, afternoon shade is especially helpful. It may slowly grow into a clump over time, especially in loose-ish soil, but that slow increase is usually what we refer to as “naturalizing,” not aggressive invasion. 

For those of us wanting to avoid invasive plants, this is the important distinction: Bletilla striata can spread, but it is generally described as modest and manageable. It is not the kind of plant that usually demands urgent removal from a home landscape.

Eulophia graminea: Attractive, Adaptable, and Invasive Drama Queen

Eulophia graminea may also look interesting to gardeners. It is a terrestrial orchid with grasslike leaves, large pseudobulbs, and tall flower spikes carrying many small flowers with pale, greenish, brownish, white, or pinkish tones. It is native to tropical and subtropical Asia, but it has become established in parts of Florida after first being recorded there in the 2000s. 

The problem is not that it looks weedy at first glance. In fact, one reason most people let it grow is curiosity: an unexpected orchid in mulch, turf, or a landscape bed. Too good to be true! But this plant produces very fine seeds that can be carried by wind, and it has been found in mulched beds, disturbed areas, open grasslands, beaches, and natural communities. Once a plant flowers and sets seed, the opportunity for spread increases dramatically.

Florida invasive-plant resources classify Eulophia graminea as a plant of concern. UF/IFAS Extension advises removing it before flowering and seed set, bagging it for trash disposal rather than composting it. For us, that means this orchid should not be treated as a lucky volunteer to nurture; it should be treated as a risk. This orchid has been showing up in packaged mulch and was most recently sighted in Montgomery County.

Phaius tankervilliae:   The Nun’s Orchid 

Phaius tankervilliae, is commonly called nun’s orchid or nun’s-hood orchid. It is a large terrestrial orchid with broad, pleated leaves and tall flower spikes that can carry many showy, hooded flowers in white, brown, mauve, pink, and yellow tones. Compared with Bletilla striata, it is much more tropical in feel and scale.

 Phaius tankervilliae is usually a specimen plant rather than a groundcover. It likes bright filtered light or light shade, evenly moist but well-drained organic soil or potting mix, and warm conditions. It can be grown outdoors but should be protected from hard freezes.

Its invasive status is more nuanced than Eulophia graminea. It is not presented as the same immediate removal target as Chinese crown orchid, but some horticultural and orchid references note that Phaius tankervilliae has become invasive in places with light frost. 

The Takeaway?

To stop the spread of invasive plants, we need everyone’s help.

Identify and Report

1. Watch for unfamiliar sprouts and volunteers, especially in mulch, turf, landscape beds, and disturbed areas. Invasive plants can arrive from many sources and spread quickly.
2. Confirm the plant before acting. Use a plant-identification app such as Seek by iNaturalist, Google Lens, or Plant ID to compare the plant with reliable references, or ask for help if you are unsure.
3. Report suspected invasive orchids with clear photos and location details.
4. Fort Bend County Master Gardeners Helpline: 281-341-7068 or FortBendmg@fbmg.org
5. Texas Invasives: https://texasinvasives.org/

Remove and Dispose Safely

1. If you identify Eulophia graminea or another invasive orchid with flower stems, remove it before it sets seed whenever possible.
2. Cut flowering or seed-bearing stems at the base, place them in a plastic bag, seal the bag, and put it in the trash.
3. Dig up the remaining plant carefully, including pseudobulbs and roots, and avoid leaving plant pieces in the soil.
4. Do not compost invasive plant material. Bag and trash stems, seed heads, fruits, cuttings, and any plant parts that could re-sprout or spread.
5. Monitor the area for new sprouts and repeat removal as needed.
6. Tell neighbors and friends what to watch for so they can help prevent spread.

Acknowledgements

• https://texasinvasives.org/
• Missouri Botanical Garden Plant Finder entry for Bletilla striata
• Gardenia plant profile for Bletilla striata
• UF/IFAS Extension Hillsborough County guidance on Chinese crown orchid
• Florida Natural Areas Inventory invasive species profile for Eulophia graminea
• UF/IFAS Extension guidance on nun’s orchid
• American Orchid Society Phaius culture guidance
• Gardenia plant profile for Phaius tankervilleae