Commonly found in the Ozarks and prairie regions of Missouri in open woodlands, savannas, glades and prairies. It’s also called devil’s shoe lace because of the small prickles on older stems. Plant tends to creep across the ground and over nearby vegetation. Sensitive briar is a good food source for wildlife and nectar source for insects.
Alternative name: Mimosa quadrivalvis
SENSITIVE BRIER (MIMOSA NUTTALLII)
Sensitive brier has a lot going for it. The flashy flowers are bright pink, the foliage responds to your touch and it provides forage for wildlife. That’s a lot to like about this little trailing plant.
Latin Name/Common Name- The genus name Mimosa is Greek in origin and means “mimic”. Nuttallii honors Thomas Nuttall, the English botanist who studied plant life in the US in the 1800’s. The common name “Sensitive brier” was given because the leaves fold up when disturbed. It is also known as Devil’s shoestrings and Cat’s claw or Catclaw brier because of the prickles on the trailing stems. Mimosa nuttallii is a perennial in the legume (bean) family.
Bloom Color- There is nothing bashful about the flowers of Mimosa nuttallii. Each blossom is a globe composed of hot pink filaments with prominent yellow anthers at each tip.
Bright pink globes with yellow tips
Macro image of the pink filaments and two-lobed yellow anther
Description- Mimosa nuttallii is a creeping plant with a length of 4 to 5 feet. The stem is variably green or pink and is covered with recurved prickles.
The alternate leaves are bipinnately (twice pinnate) compound. This means that each leaf is divided into primary leaflets which are further divided into secondary leaflets.
The leaves of Mimosa nuttallii respond to various stimuli by folding along the primary leaflet. You can initiate this reaction simply by touching a leaf. The folding also may occur due to wind or darkness- the leaves fold up at night. This reaction is termed seismonasty and is quite common in the Mimosaceae family. You can read more about seismonasty in plants here- http://en.wikipedia.org/wiki/Thigmonasty.
The flowers of Mimosa nuttallii arise on long stalks at the leaf axils. Before blooming, the buds somewhat resemble green bramble fruits such as blackberry.
Blooms, buds and spent flowers along a stem
Bloom Time- Mimosa nuttallii may be found in bloom from mid-May to early September.
Habitat- Open fields and dry, rocky areas are preferred habitat for Sensitive briar. It is also seen growing at woodland margins.
Mimosa nuttallii thriving on dry, rocky ground
What’s Growing Nearby? Grasses and sedges are found growing alongside Mimosa nuttallii. I’ve also seen another interesting plant- Spider Milkweed (Asclepias viridis) thriving nearby in the same open field.
Mimosa nuttalli mixing with grasses in an open field
Spider milkweed growing alongside Sensitive brier
Endangered List- The USDA Plants Conservation site does not have a page showing the Legal Status for Mimosa nuttallii.
NatureServe lists Mimosa nuttallii as Critically Imperiledin Iowa. Unfortunately, it’s not ranked in nearly all the rest of its habitat, so we cannot know the true conservation status of this interesting plant.
Interesting Tidbits- Mimosa nuttallii provides forage for deer and turkey. Bobwhite quail consume the seeds and the nectar is important for many insects. It is also nutritious for livestock; although, how they eat the briers, I don’t know. Nevertheless, its absence in a field is a good indicator of overgrazing. The flowers are very attractive to birds, bees and other insects
Sensitive Plant (Mimosa pudica) is a member of the Mimosa genus. The stout plant generally grows up to 24-36 inches tall, producing delicate, fern-like leaves and fluffy pink or purple flowers. Sensitive plant is a popular houseplant due to its remarkable leaves, which curl into themselves when touched.
As the common name suggests, the leaves close when they are touched.
Mimosa pudica prefers an average room temperature between 65 to 75 degrees Fahrenheit. Though it will grow outdoors in U.S. Department of Agriculture plant hardiness zones 9 to 11, it has a tendency to spread aggressively and may become weedy. The plant may be grown outdoors as an annual in USDA zones 2 to 8.
Sensitive plant should be planted in well-draining loamy soil enhanced with peat moss to improve drainage. Water regularly to keep the soil moist, but not water logged. Growth can be enhanced with a high-potassium liquid fertilizer diluted to about half strength with water, applied to the soil every two weeks during the growing season. Always water first before fertilizing to avoid burning the roots.
Sensitive plant may be propagated by seed indoors any time of the year. Seeds are quite tough, and should be nicked with a knife to help improve germination success. Seeds may also be placed in hot water and soaked overnight. Place seeds in a moist soil medium, cover with a light sprinkle of soil and place in a warm, bright location. Seeds generally take about a week to germinate
Germination:
1. Place your seeds in warm water to soak for 8-12 hours.
2. Gently place your seeds barely under the soil, about 1/8 of an inch deep.
3. Gently water or mist the soil. Keep your soil moist but not overly wet. Flower pots or pellets should not be sitting in water.
4. Keep the seeds and soil in the sunniest and warmest location possible. Keep the temperature as close to 70 degrees or above.
5. You can try this with some of your plants: to add warmth and humidity when not using a Sensitive/ Shy Plant Greenhouse or Grow Kit, put a plastic bag over the top of your flower pots to keep in moisture and warmth; when doing this, make sure they don’t overheat in the direct sunlight.
6. The first leaves should sprout in about a week (these are not Shy). However, even these small Sensitive / Shy sprouts will begin “sleeping” at night, by closing their leaves.
8. In several weeks, the Sensitive/ Shy sprout will grow and move when they are tickled. Expect your plants to grow slowly during the winter season and to grow rapidly once the spring arrives!