Lupinus hirsutissimus, commonly known as the hairy lupine, is a species of flowering plant in the Fabaceae family. Native to western North America, it is predominantly found in California and Oregon. The plant typically grows up to 1 meter tall and features hairy stems and leaves. Its flowers are arranged in tall, spike-like inflorescences that can reach up to 30 cm in length, with each flower displaying five petals that are usually blue or purple with white markings.
The hairy lupine thrives in well-drained soils and is commonly found in open areas such as meadows, grasslands, and along roadsides. It can grow at elevations ranging from sea level up to 2,500 meters.
This plant serves as an important food source for various wildlife species, including deer and rabbits, which feed on its leaves. Additionally, its nectar-rich flowers attract bees, aiding in pollination.
Indigenous people have used Lupinus hirsutissimus for medicinal purposes, particularly for treating skin conditions such as eczema and psoriasis, due to its anti-inflammatory properties.
Overall, Lupinus hirsutissimus is a significant native species with ecological importance in supporting wildlife populations and cultural significance through its traditional medicinal uses by the indigenous people of western North America.
Stinging annual lupine demonstrates strong disease resistance and is usually not prone to illnesses. Still, it can be vulnerable to pests and diseases found in its surroundings. These infections tend to be mild. For care, the plant requires moderate maintenance. It should be pruned regularly to keep a tidy appearance and support healthy growth. Fertilizing can also encourage flowering. This lupine is well suited to anyone with outdoor space, such as a garden or patio, and does not demand extensive care experience. When grown indoors, it may need additional attention.
How to keep Lupinus Hirsutissimus.
Light
The stinging annual lupine does best in spots that receive unobstructed sunlight all day. This condition is essential for healthy growth and development at every stage. In its native surroundings it is usually subject to that continuous sun. Too much sun does not harm it, while too little light can cause poor growth.
Water
The stinging annual lupine thrives in arid environments by adapting to conserve water. Although it can tolerate short periods of drought, it needs weekly watering. This herbaceous plant is typically grown outdoors, where it benefits from natural rainfall, but it requires irrigation during prolonged dry spells.
Temperature
The stinging annual lupine performs best in its native habitat when temperatures are generally between 68 and 95 °F (20 to 35 °C). During colder months, providing indoor protection or increasing its exposure to sunlight can help keep it healthy.
Fertilizer
When most of the blooms on the Stinging annual lupine are fully open, resume fertilizing. Around the period when blooms are at peak production, apply fertilizer every three to four weeks, as weather permits. Then, once the Stinging annual lupine begins to produce fewer new blooms, stop fertilizing; there’s no need to feed the plant when it can no longer produce more flowers.
Pruning
To promote growth and blooming, prune stinging annual lupine from early to late spring. Trim any dead or damaged stems to improve airflow and light penetration, reducing the risk of disease. This preparation ensures a healthier and more attractive plant for the vigorous growing season ahead.
Botanical profile.
- Plant Type
- Herb
- Life Cycle
- Annual
- Genus
- Lupinus
- Family
- Fabaceae
- Hardiness Zone
- 7
- Mature Height
- 20 cm to 91 cm
- Mature Spread
- 61 cm
- Leaf Color
- Green, Dark Green
- Leaf Type
- Deciduous
- Flower Color
- Blue, Purple
- Flower Size
- 1.02 cm to 2.03 cm
- Bloom Time
- Spring
- Planting Time
- Spring, Summer
- Harvest Time
- Late spring, Early summer, Mid summer
- Native Area
- Mexico
Other names.
Reader questions.
How often should I water my Stinging annual lupine plant?
To keep your Stinging annual lupine healthy, it's important to water it regularly. In the spring, watering once a week should be sufficient. However, as the weather gets warmer, you may need to increase watering to two or three times a week. Be careful not to overwater, as this can harm the plant. Regardless of how often you water, ensure that the soil remains moist but not overly wet. When it comes to watering Stinging annual lupine in a pot, you'll need to water more frequently compared to plants in the ground. Potted plants dry out faster, so plan to water them a few times a week, rather than just once a week for plants in the ground.
What are the sun requirements for stinging annual lupine?
Stinging annual lupine thrives in full sun, requiring more than 6 hours of sunlight per day for optimal growth. However, it can also survive in partial sun, which means about 3-6 hours of sunlight daily. It's important to observe how sunlight moves through your garden and choose planting spots that provide a perfect balance of light and shade, ensuring the plants' happiness.
What is the ideal temperature range for stinging annual lupine?
The stinging annual lupine, scientifically known as Lupinus hirsutissimus, thrives best in its native growth environment with temperatures typically ranging from 68 to 95°F (20 to 35°C). It shows strong cold resistance and generally does not require special frost protection measures during winter. However, it's important to ensure that during colder months, if indoor protection is not possible, the plant receives increased sunlight exposure to maintain its health.
How should I water my Stinging annual lupine plant?
To water Stinging annual lupine, you have several options. You can use a garden hose with a spray nozzle, a watering can, or any common watering tool. These plants aren't too fussy about their water source – they can thrive with rainwater, tap water, or filtered water. However, try to avoid watering them from above as it may harm the leaves and flowers and could even cause disease. Instead, consider using a drip irrigation system, which provides even and direct water to the soil, ideal for Stinging annual lupine. If you have a container-grown lupine, the same principles apply, but you can use a cup, watering can, or tap to water the soil directly.
What essentials should be considered for growing stinging annual lupine?
Stinging annual lupine requires locations where sun rays are fully unobstructed throughout the day. This full sun exposure is critical for its growth at all stages, mimicking its native habitat's conditions. While it tolerates excessive sun exposure without negative impacts, inadequate sunlight can lead to poor growth. For indoor plants, where natural light may be insufficient, especially in winter or less sunny spaces, using artificial lighting is pivotal. LED lights are recommended for indoor plant lighting, with varying wattage requirements based on plant type: 30-50W/sq ft for full sun plants, 20-30W/sq ft for partial sun, and 10-20W/sq ft for full shade plants. The artificial light source should be placed 12-36 inches above the plant, mimicking natural sunlight for 8-12 hours per day.
How should stinging annual lupine be cared for in winter?
Stinging annual lupine is cold-tolerant and can usually withstand winter without special frost protection measures. If winter temperatures are expected to drop below -15°C, providing cold protection by covering the plant with soil or straw is advisable. Additionally, before the first freeze in autumn, it is recommended to water the plant abundantly, ensuring the soil remains moist and enters a frozen state. This practice helps prevent drought and water scarcity for the plant during winter and early spring.
What do I do if I give my Stinging annual lupine too much or too little water?
To avoid underwatering your Stinging annual lupine, simply water it more regularly when you notice it lacks moisture. Overwatering is a more serious problem that can result in diseases and the plant's decline. Prevent this by choosing a suitable growing location with plenty of sunlight and good drainage. If your potted Lupine is overwatered, consider repotting it with loose soil and a pot that drains well.
What are the key symptoms of light deficiency in stinging annual lupine?
Stinging annual lupine shows several symptoms when light is inadequate, including smaller new leaves, leggy or sparse growth, faster leaf drop, slower or halted new growth, and lighter-colored or chlorotic new leaves. Symptoms of excessive sunlight include sunscald, which appears as pale, bleached, or necrotic areas on the plant, leaf curling as a defense mechanism to minimize water loss, wilting due to increased transpiration, and leaf scorching characterized by brown, dry, crispy edges on leaves.
What are the symptoms of stinging annual lupine at low temperatures?
At low temperatures, stinging annual lupine, which is cold-tolerant and thrives best above 20°C, should be kept above 0°C during winter. If temperatures fall below -15°C, you may not notice any immediate changes during winter; however, there could be a decrease in sprouting or even no sprouting at all come spring. The solution for spring is to remove any parts of the plant that have failed to sprout.
How much water does my Stinging annual lupine require?
There are a few ways to figure out how much water your Stinging annual lupine needs. Some gardeners prefer to check the moisture level of the soil by feeling it. This method suggests watering until the top six inches of soil feels moist. Another option is to use a specific measurement. On average, Stinging annual lupine requires about two gallons of water per week, depending on heat and soil dryness. However, following this guideline too strictly may result in overwatering if your plant needs less. When growing Stinging annual lupine in a container, a different approach is needed. You should water until all layers of dry soil are moistened. You can test this by sticking your finger in the soil or by looking for a slight trickle of excess water from the drainage holes.
How can you address light-related issues for stinging annual lupine?
To address light-related issues, for indoor stinging annual lupine, gradually move the plant to a sunnier location each week until it gets at least 6 hours of direct sunlight daily, utilizing a south-facing window for maximum exposure. Artificial lights, like desk or ceiling lamps, can be used for at least 8 hours daily for additional lighting. Outdoors, move plants gradually to sunnier spots to avoid sunburn, ensuring they adapt properly to the increased light intensity. If sunlight is obstructed, for ground plants, consider pruning trees that block sunlight or transplanting smaller plants to sunnier locations during their dormant period to ensure ample sunlight and good drainage.
How does high temperature affect stinging annual lupine and how should it be managed?
During summer, it is crucial to keep the stinging annual lupine below 35°C. Exceeding 38°C can cause the leaves to lighten in color, become prone to curling, suffer from sunburn, and in severe cases, cause the entire plant to wilt and dry out. To manage high temperatures, trim away the sunburned and dried parts of the plant. Move it to a location that offers shade during the midday and afternoon sun, or use a shade cloth. Ensure the soil is kept moist by watering the plant in the morning and evening.
