Shrimp Plant (Justicia brandegeeana): Detailed Guide to Its Appearance and Summer Care

The shrimp plant's bracts are numerous and overlapping, so its appearance closely resembles a shrimp's shell, which is how it got its name. Although the shrimp plant is not often seen in daily life, its ornamental value is still relatively high, and some flower enthusiasts keep shrimp plants as potted plants on their balconies.

Shrimp Plant

1. Morphological characteristics: The shrimp plant has a peculiar, lively form resembling a shrimp. Grown as an indoor potted ornamental, it blooms continuously all year round. The leaves are opposite, ovate or long elliptic, soft in texture, with a relatively rough surface, entirely green, light green. The spike inflorescence is terminal and drooping; the bracts are numerous and overlapping, shaped like a shrimp's shell, ranging from brick red to dark red or yellow-green, and are the main ornamental part. The corolla is slender, extending beyond the bracts, lip-shaped, white, with purple spots at the throat of the lower lip. It blooms all year round and rarely sets seed.

2. Summer care for potted plants: In summer's high temperatures, water frequently. When watering, be careful to spray water on the pot surface, the plant, and the ground around the pot; spraying a fine mist on the plant in particular can make the branches, leaves, and flowers fresher and more vivid, further enhancing the ornamental effect. Spraying water can increase the air humidity in a small area and also lower the temperature, which benefits the growth of potted shrimp plants and their bud formation and blooming. Summer's heat and strong light mark the shrimp plant's peak growing period, so the shrimp plant should be given appropriate shading for its flowers to bloom better. When the temperature rises, the pot can be moved to a cool, well-ventilated spot with scattered light.

Key Points for Summer Care of Potted Shrimp Plants

Morphological Characteristics and Cultivation Methods of the Shrimp Plant: How to Propagate the Shrimp Plant

The shrimp plant belongs to the genus Justicia in the family Acanthaceae. Its red bracts overlap in drooping strings, and the inflorescence is about 10 cm long, resembling a lobster or a fox's tail, which is very interesting. It blooms all year round and is suitable for potting, placed on a high indoor shelf for viewing, and can also be used in flower bed arrangements.

The shrimp plant likes a warm, humid environment, with a minimum temperature of 5°C to 10°C. It likes light but avoids scorching sun, and has a certain shade tolerance. The shrimp plant has strong resistance and few pests and diseases. When growing it in a greenhouse, attention should be paid to controlling scale insects and red spider mites.

Morphological Characteristics of the Shrimp Plant

The shrimp plant is an evergreen subshrub, 1-2 m tall, entirely covered with hairs. The stem is round, slender and weak, much branched, with the bases of the nodes on young stems red-purple. The leaves are ovate, with a short pointed tip, a wedge-shaped base, and entire margins. The spike inflorescence is terminal, 6-9 cm long, drooping, with persistent bracts in brown, red, yellow-green, and yellow.

The shrimp plant's flowers are white, extending beyond the bracts. The flower is divided into upper and lower lips; the upper lip is entire or slightly lobed, and the lower lip is shallowly lobed with 3 rows of purple markings. The stem is round, much branched at the base, with short coarse hairs. The leaves are 2.5-6 cm long, entire, with short hairs on both sides. The spike inflorescence droops, with bright, brown-red persistent large bracts; the bracteoles are ovate-lanceolate; there are 5 calyx lobes with fine hairs; the corolla is white, extending beyond the bracts, with short hairs outside, lip-shaped, the upper lip entire or slightly lobed, the lower lip shallowly lobed with 3 rows of purple markings; 2 stamens.

Ecological Habits of the Shrimp Plant

The shrimp plant likes moisture, is fairly drought-tolerant, and prefers loose, fertile, well-drained neutral and slightly acidic soil. It grows in full sun or partial sun, likes warm, humid environments, and is cultivated in greenhouses. The minimum temperature needs to be 5-10°C, and the suitable growing temperature is 18-28°C. It likes sunlight and is also fairly shade-tolerant, avoids scorching sun, and likes moisture.

The shrimp plant blooms continuously all year round, and its fruiting period is year-round.

Cultivation Methods for the Shrimp Plant

Potted Plant Care

The shrimp plant likes sunlight, and likes a mild, humid climate and well-ventilated environmental conditions. Its growth and development temperature is 10°C to 27°C, and around 20°C its growth is most suitable. The suitable temperature during the summer-autumn growing period is around 25°C, and 10°C to 23°C in winter and spring, with a relative humidity of about 70%. After the autumn cool arrives, it can be exposed to direct light. If the room temperature is kept above 10°C and fertilizer and water management is continued and strengthened, the plant can continue to produce buds and bloom. If in winter the room temperature can only be kept at around 5°C, then fertilization must stop and the potting soil should be kept slightly dry, so the plant can overwinter safely. It has a certain cold tolerance; in various parts of North China it is grown as a potted plant in greenhouses, while in the Nanjing area it can overwinter outdoors.

The shrimp plant likes loose, fertile sandy loam with good water and air permeability. For potting soil, mix 4 parts leaf mold, 3 parts garden soil, 1 part decomposed organic fertilizer, 1 part sandy soil, and 1 part fresh sawdust into a slightly acidic growing medium. Then place some pieces of livestock hoof and horn and crushed bone at the bottom of the pot as base fertilizer; the fertilizer effect lasts a long time and is more suitable for its growth and bud formation and blooming.

Potted shrimp plants should be given full light in spring and autumn. If the plant is too shaded and light is insufficient, the stems and leaves tend to grow leggy, which not only affects the beauty of the plant's shape but also affects the quality and quantity of blooming.

Fertilizer and water management for potted shrimp plants should be appropriate. The shrimp plant's growing period and blooming period are both long, and it needs relatively more fertilizer and water. Normally keep the potting soil slightly moist, and apply a decomposed cake fertilizer solution once every 7 to 10 days. When blooming, add phosphorus fertilizer to the fertilizer solution to make the flowers more vivid. In summer, be careful to water frequently. To create a good environmental climate, when watering, be careful to spray water on the pot surface, the plant, and the ground around the pot; spraying a fine mist on the plant in particular can make the branches, leaves, and flowers fresher and more vivid, further enhancing the ornamental effect. Spraying water can increase the air humidity in a small area and also lower the temperature, which benefits the growth of potted shrimp plants and their bud formation and blooming.

Doing a good job of shading and ventilation for the shrimp plant in summer is an important part of growing it well. During this period, if care is not thorough, the plant will grow poorly and shed leaves, affecting its blooming. Entering summer is also the shrimp plant's peak growing period, when bright, peculiar flowers bloom in profusion. When the summer high temperature reaches around 35°C and the sunlight is strong, this is very unfavorable for the shrimp plant's blooming, so the work of shading and ventilating the shrimp plant must be done well. Whenever the sunlight is strong and the temperature rises, the pot can be moved to a cool, well-ventilated spot with scattered light. If there are many potted flowers, a shed can be built above to shade the seedlings, shading in the morning and uncovering in the evening. During the plum rain season, the weather is often uncertain between overcast and clear; when it is cloudy, roll up the curtain, and when it clears, put up the curtain promptly. Although this is time-consuming and labor-intensive, it benefits the plant's growth. If the shrimp plant is grown indoors, the pot can be placed in a cool, bright, well-ventilated spot or on a coffee table or desk a little farther from the window, and it can still grow normally and bloom abundantly and vividly.

If the shrimp plant is planted in the ground, the plant is tall and its branching ability is very strong, and it blooms very readily. Therefore, when potted, it should be pruned and shaped frequently, cutting off overly long and tall branches and spent flowering branches, so that the plant's shape is short, sturdy, and well-proportioned. The shrimp plant's clumping nature is relatively weak, and new shoots tend to grow leggy easily, making the plant's posture loose with few flowers. Therefore, it should be cut back at the right time and pinched back moderately to develop a low, compact plant shape. For multi-year-old plants, a frame can also be set up for tying.

Propagation Methods for the Shrimp Plant

1. Cuttage propagation

As long as the temperature is suitable, cuttings can be taken in all four seasons, but mainly in spring and summer. If taking cuttings in summer, attention should be paid to shading and keeping moist. Cut 2- to 3-node shoot segments of the current year's well-developed growth as cuttings. Both old branches and tender branches can be used for cuttings; under the same temperature conditions, tender branches root faster. Insert the basal 1 node into plain sand, and at a room temperature of 20°C, they will root in about 10 days and bloom the following year. Yellow sand, vermiculite, or perlite can all be used as cutting media, and for tender-branch cuttings the medium must be strictly sterilized. After the cuttings root, transplant them into pots in a timely manner and shade them appropriately; once new leaves grow, move them to a spot with ample sunlight.

Post-Cutting Management

Temperature

The optimal temperature for cutting rooting is 20°C-30°C. Below 20°C, cuttings root with difficulty and slowly; above 30°C, the upper and lower cuts of the cuttings are easily infected by pathogens and rot, and the higher the temperature, the greater the proportion of rotting. When low temperatures are encountered after cutting, the main measure for keeping warm is to wrap the flower pot or container used for cutting with plastic film; when the temperature is too high after cutting, the main measure for cooling is to shade the cuttings, blocking out 50-80% of the sunlight, and at the same time misting the cuttings 3-5 times a day; on clear days with higher temperatures, mist more often, while on cloudy and rainy days with lower temperatures and higher humidity, mist less often or not at all.

Humidity

After cutting, the relative air humidity must be maintained at 75-85%. The basic requirement for cutting rooting is that before the cuttings root, they must be kept fresh and tender so they can carry out photosynthesis to produce rooting substances. However, cuttings that have not rooted cannot absorb enough water to maintain their internal water balance, so misting must be used to reduce the cuttings' water evaporation: under shaded conditions, mist the cuttings 3-5 times a day; the higher the temperature on clear days, the more often you mist, while the lower the temperature on cloudy and rainy days, the less often you mist or not at all. But excessive misting makes cuttings susceptible to infection by pathogens and rot, because many kinds of pathogens exist in water.

Light

Cutting propagation cannot do without sunlight, because the cuttings still need to continue photosynthesis to produce nutrients and rooting substances to supply their rooting needs. However, the stronger the light, the higher the temperature inside the cuttings, the more vigorous the transpiration of the cuttings, and the more water they consume, which is unfavorable for the cuttings' survival. Therefore, after cutting, 50-80% of the sunlight must be blocked out. After the root system grows, gradually remove the shade net: on clear days, remove the shade net at 4:00 pm each day, and put the shade net back before 9:00 am the next day.

2. Seed propagation

Before sowing, the seeds must first be selected. Whether the seeds are well chosen directly relates to whether sowing will succeed. It is best to use seeds harvested in the current year. The longer the seeds are stored, the lower their germination rate. Choose seeds that are plump, free of damage or deformity, and free of pests and diseases. Soak the seeds in warm hot water (at a temperature similar to face-washing water) for 12-24 hours, until the seeds absorb water and swell.

For very common seeds that germinate easily, this step can be skipped. For tiny seeds that are hard to pick up with your hands or other tools, dampen one end of a toothpick with water and stick the seeds one by one onto the surface of the medium, then cover with medium 1 cm thick, then place the sowing pot into water with a depth of 1/2-2/3 of the pot's height, letting the water slowly seep up. For larger seeds that can be picked up with your hands or other tools, place the seeds directly into the medium and sow them in spots at a spacing of 3 x 5 cm. After sowing, cover with medium at a thickness of 2-3 times the size of the seeds. After sowing, use a sprayer or a fine-holed watering can to moisten the sowing medium. Later, when the potting soil is slightly dry, water again, still being careful not to water too forcefully, so as not to wash the seeds out.

Post-Sowing Management

After sowing in late autumn, early spring, or winter, when a cold wave and low temperatures are encountered, the flower pot can be wrapped in plastic film to help keep warm and moist; after the seedlings emerge, promptly uncover the film, and let the seedlings receive sunlight before 9:30 am each day or after 3:30 pm, otherwise the seedlings will grow very weak and tender; after most of the seeds have sprouted, appropriate thinning is needed: pull out the diseased and unhealthy seedlings so that the remaining seedlings have a certain amount of space between them; when most of the seedlings have grown 3 or more leaves, they can be transplanted.

3. Layering propagation

Select a robust branch, and from about 15-30 cm below the tip, peel off a ring of bark. The width of the wound after peeling is about 1 cm, and the depth should be just enough to peel off the outer bark. Cut a piece of plastic film 10-20 cm long and 5-8 cm wide, put some moistened garden soil on it, and wrap and bind the girdled part like wrapping a wound, tying the upper and lower ends of the film tightly, with the middle bulging. Roots form in about 4 to 6 weeks. After rooting, cut off the branch together with its root system, and it becomes a new plant.

Potted shrimp plants are usually propagated by cuttings. Apart from the hot, humid period of midsummer, this can be done throughout the year and takes root easily, with spring and autumn being the most suitable. Generally, after the peak blooming period in June, in combination with shaping and pruning, select robust branches of the current year as cuttings, remove the leaves from one node, and insert them into loose media such as plain sand or vermiculite. After inserting, cover with film to keep warm and moist, provide light shade, and they will root; transplant them in a timely manner, and they will bloom the following year. The shrimp plant's tip has a short point, is wedge-shaped, and has entire margins. The base is much branched, with short coarse hairs. The margins are entire, with short hairs on both sides. The spike inflorescence droops, with short hairs outside, lip-shaped, the upper lip entire or slightly lobed, the lower lip shallowly lobed. The optimal temperature for cutting rooting is, spike-grown. When low temperatures are encountered after cutting, the main measure for keeping warm is to wrap what is used for cutting with plastic film; after cutting, temperature, mist the cuttings, cannot do without sunlight, because the cuttings still need to continue producing and rooting substances to supply their rooting needs. However, the stronger the light, the more inside the cuttings, the more water they consume, which is unfavorable for the cuttings' survival.

4. Division

Division propagation can also be done in spring in combination with repotting, dividing a large clump of the mother plant into several small clumps and planting them separately; they can be enjoyed in the same year.

The Flower Language of the Shrimp Plant

Shrimp plant flower language: the distress of love, drinking alone under the moon.

After reading the above introduction to the shrimp plant's morphological characteristics and cultivation methods, do you have a better understanding of how to grow the shrimp plant? If you want to know more about the shrimp plant, please keep following us.