Althaea cannabina
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Althaea cannabina

Palm-leaf-marshmallow · Hemp-leaf-marshmallow · Palm-leaf marshmallow · Palmleaf Marshmallow · Hemp-leaved marshmallow

Tier 1 Difficulty: medium Water: low Light: full_sun
Water every
7 days
Temperature
5–32 °C
Soil pH
6–7
Hardiness
Zone 4–8
Click count
198
Observations
1,172

Description

Source: leafsnap

Althaea cannabina, commonly known as the hemp-leaved marshmallow, is a perennial herbaceous plant that belongs to the Malvaceae family. Native to Europe and Asia, this plant can grow up to 1.5 meters in height. Its thick stems and large leaves resemble those of hemp plants, which is how it gets its common name. The flowers of Althaea cannabina are pink or white and bloom from July to September. They are arranged in clusters at the ends of long stems and feature five petals with a distinctive heart-shaped base. For centuries, Althaea cannabina has been used for medicinal purposes due to its high mucilage content, making it an effective remedy for coughs, sore throats, and other respiratory ailments. The roots have also been used as a natural remedy for digestive issues such as constipation. This plant prefers moist environments like marshes or riverbanks but can also thrive in well-drained soils with plenty of sunlight. Its tall stature and showy flowers attract pollinators like bees, adding to its appeal in gardens. Overall, Althaea cannabina is an interesting herbaceous perennial that offers both ornamental and medicinal benefits, making it a valuable addition to gardens both aesthetically and functionally.

Care Guide

💧 Water Every 7 days

The palm-leaf marshmallow flourishes in moderate climates, where consistent moisture is key. To maintain the soil's even moisture, it requires weekly watering. While it can endure brief dry periods, regular watering during its active growing season ensures optimal growth and lush foliage.

Suggested frequency: Every 7 days
FAQ
How should I water my Palm-leaf marshmallow plant?

To ensure the Palm-leaf marshmallow plant thrives, follow these watering guidelines: Use filtered water at room temperature. This is important because tap water may contain harmful particles. The plant prefers warm water since it originates from a warm environment. Cold water can be a shock to its system. Avoid overhead watering, as it can lead to issues with the foliage. Instead, apply filtered, room temperature water directly to the soil until it is completely soaked. This helps moisten the roots and support their growth and nutrient absorption.

What should I do if I give my Palm-leaf marshmallow plant too much or too little water?

Both overwatering and underwatering can harm the health of your Palm-leaf marshmallow, but overwatering is a more common issue. When this plant receives too much water, its stems and leaves may wilt and turn yellow. Overwatering for a long time can also cause diseases like root rot, mold, and mildew, which can kill your plant. Palm-leaf marshmallow is less likely to be underwatered because it can tolerate drought well. However, underwatering is still possible and may result in brittle, brown leaves. It's important to notice the signs of overwatering early when caring for your Palm-leaf marshmallow. Diseases like root rot may not be fixable if you wait too long. If you see signs of overwatering, reduce your watering schedule and check the soil's drainage. Replace poorly draining soil with a loose, well-draining potting mix. If you notice signs of underwatering, water the plant more regularly until the signs improve.

How often should I give water to my Palm-leaf marshmallow?

If your Palm-leaf marshmallow is in a pot, the most precise way to determine if it needs water is by checking the soil moisture with your finger. If the top two to three inches of soil are dry, it's time to water it. On the other hand, if your Palm-leaf marshmallow is grown outside in the ground, you can use the same method to check the soil moisture. If the top few inches of soil have dried out, it's time to give it some water. Typically, during spring and early fall, you'll need to water this plant about once a week using this method. However, during extremely hot weather, you might need to water it twice a week or even more frequently. It's worth noting that mature, well-established Palm-leaf marshmallows have a remarkable ability to withstand drought.

How much water does my Palm-leaf marshmallow plant need?

When watering your Palm-leaf marshmallow, it's important to be generous with the amount of water you give. Make sure the first two to three inches of soil are dry, then give a thorough watering that completely soaks the soil. Aim to add enough water so that it flows through the drainage holes at the bottom of the pot. If you don't see excess water draining, it means you might not have watered enough. However, be careful not to let water accumulate in the soil, as this can harm the plant. Also, if water doesn't drain properly, it could mean the soil isn't draining well, which is bad for the plant's health. Lastly, if the plant is outdoors, providing 1 inch of rain per week should be sufficient.

How do I water my Palm-leaf marshmallow plant as it grows?

The water needs of the Palm-leaf marshmallow vary depending on its growth stages. In the first few years and after being transplanted, it requires more water. This is because it is focused on developing new roots to support future growth, and these roots need extra moisture. However, as the plant matures, it needs less water. Additionally, during the bloom period, when the plant is developing flowers, it will require more water to accommodate the increased moisture demands.

☀️ Light Full sun

Palm-leaf marshmallow does best in places that receive abundant sunlight for most of the day. It can tolerate partial sun exposure, though that is not as favorable. Having evolved in areas with frequent sun exposure, palm-leaf marshmallow needs steady light to grow vigorously. Both too much and too little sun can harm its health.

Ideal: Full sun
FAQ
What are the sunlight requirements for Palm-leaf marshmallow?

Palm-leaf marshmallow requires full sun, which is above 6 hours of sunlight, for optimal growth, but it can also tolerate partial sun, about 3-6 hours of sunlight. It's essential to observe how sunlight moves through your garden to ensure that you choose spots providing the right balance of light and shade for these plants. Originating from habitats with frequent sun inundation, consistent illumination is crucial for the plant’s robust growth. Both over and underexposure to the sun can negatively affect its health.

Can Palm-leaf marshmallow thrive under artificial lighting?

Yes, Palm-leaf marshmallow can thrive under artificial lighting, especially when natural sunlight is insufficient. This is particularly useful in winter or less sunny spaces. Artificial lights, like LED lights, are a popular choice as they can provide specific wavelengths needed for the plant's growth. For optimal growth under artificial light: full sun plants need 30-50W/sq ft, partial sun plants 20-30W/sq ft, and full shade plants 10-20W/sq ft. The light source should be placed 12-36 inches above the plant to mimic natural sunlight, and the duration should mimic the length of natural daylight hours, generally 8-12 hours per day.

What are the symptoms of insufficient or excessive sunlight exposure in Palm-leaf marshmallow?

Symptoms of insufficient sunlight exposure include smaller new leaves, leggy or sparse growth, faster leaf drop, slower or no new growth, and lighter-colored new leaves. Symptoms of excessive sunlight exposure include chlorosis (where leaves lose their green color and turn yellow), sunscald, leaf curling, wilting, and leaf scorching. These conditions indicate either a lack of or too much sun exposure, affecting the plant's health and ability to photosynthesize.

How can I address sunlight-related issues with my Palm-leaf marshmallow?

To address insufficient sunlight, gradually move plants to sunnier locations each week until they receive at least 6 hours of direct sunlight daily. For indoor plants, using a south-facing window or artificial light for at least 8 hours daily can help. For outdoor plants, ensuring a gradual adaptation to sunlight and avoiding sudden changes in light intensity is crucial to prevent sunburn. If sunlight obstruction is a problem, consider reducing obstructions like trees by pruning or moving smaller plants to a spot with ample sunlight and good drainage during their dormant period, usually late winter or early spring.

🌡️ Temperature 5–32.2°C

Palm-leaf marshmallow is native to temperate environments and generally prefers temperatures between 41 and 89.6 °F (5 to 32 ℃). Extreme temperatures may require seasonal adjustments to ensure optimal growth.

Ideal temperature: 5–32.2°C
FAQ
What is the preferred temperature range for Palm-leaf marshmallow?

Palm-leaf marshmallow, or Althaea cannabina, thrives in temperate environments, favoring temperatures between 41°F (5°C) and 89.6°F (32°C). These conditions are ideal for its growth, as it demonstrates strong cold resistance. Therefore, the plant typically does not require special frost protection measures during winter. However, in regions where winter temperatures may fall below -30°C, it's crucial to provide additional cold protection, such as covering the plant with soil or straw. Additionally, abundantly watering the plant before the first freeze of autumn helps the soil retain moisture and prevents drought and water scarcity during the colder months.

How does Palm-leaf marshmallow respond to low temperatures?

Palm-leaf marshmallow is notably cold-tolerant, performing best in conditions above 5°C. Throughout the winter, it's essential to maintain temperatures above -25°C to ensure the plant's health and vitality. If temperatures drop below -30°C, the Palm-leaf marshmallow may not exhibit noticeable changes during the winter, but there could be a significant impact on its ability to sprout in spring. In some cases, there may be decreased sprouting or none at all. To manage this, any parts of the plant that have failed to sprout by spring should be removed to encourage healthy new growth.

What measures should be taken if Palm-leaf marshmallow experiences high temperatures?

During the summer, it is crucial to ensure that the temperature surrounding Palm-leaf marshmallow does not exceed 32°C. Exposure to temperatures above 35°C can lead to the plant's leaves becoming lighter, curling, being prone to sunburn, and, in severe scenarios, the entire plant may wilt and dry out. To mitigate these risks, sunburned and dried parts should be trimmed away. The plant should be relocated to an area with shade during the midday and afternoon hours or should be covered with a shade cloth. Moreover, watering the plant in the morning and evening will help keep the soil adequately moist, ensuring the plant remains healthy.

💨 Humidity
Humidity:
🪴 Soil 6-7
Soil pH: 6-7
🌱 Fertilizer

The best time to feed a Palm-leaf marshmallow is in early spring, as it emerges from dormancy and starts active growth. Fertilizing supplies essential nutrients for healthy development. Although Palm-leaf marshmallow has fairly low fertilizer requirements, an annual application can boost its survival and encourage better, longer-lasting flowers.

FAQ
Why should I put plant food on my Palm-leaf marshmallow?

Fertilization is important for the Palm-leaf marshmallow because it provides key nutrients for the plant's growth. Although the fertilization needs are relatively low, annual fertilization can benefit the plant by improving its overall health and promoting longer-lasting flowers. Therefore, those who want their Palm-leaf marshmallow to thrive should consider regular fertilization.

When should I fertilize my Palm-leaf marshmallow plant?

The best time to fertilize a Palm-leaf marshmallow is in late winter or early spring. This is when the plant is coming out of its dormant phase and starting to grow actively. Fertilizing at this time helps promote healthy growth and gives the plant a good start for the season. While it's generally best to fertilize in early spring, you can also fertilize in the fall if needed. However, it's not recommended to fertilize during summer or winter.

When is it not a good idea to fertilize my Palm-leaf marshmallow?

To properly care for your Palm-leaf marshmallow plant, it is important to fertilize only during the late winter and early spring. This plant has minimal fertilization needs, so one feeding per year is sufficient. It is crucial to avoid fertilizing during spring, summer, and fall as this can lead to overfertilization and subsequent complications. However, if you missed fertilizing in spring, it is acceptable to feed the plant in the fall. Additionally, there is no need to fertilize the Palm-leaf marshmallow during winter as it enters a dormant phase and does not undergo new growth.

Which fertilizer should I use for my Palm-leaf marshmallow?

When fertilizing a Palm-leaf marshmallow, a general-purpose fertilizer with balanced amounts of the main plant nutrients is usually sufficient. However, there are specific nutrient blends that can be even more beneficial. Many gardeners believe that higher levels of phosphorus help promote stronger roots and better flowers. Since Palm-leaf marshmallow is a flowering plant, using a phosphorus-rich fertilizer may be the best choice. Granular or liquid fertilizers can both be used, as long as they provide ample nutrients. Apart from manufactured fertilizers, you can also improve the soil for your Palm-leaf marshmallow using organic methods. Compost, manure, and similar materials can greatly contribute to creating a healthy growing environment for your Palm-leaf marshmallow.

How should I provide nutrients to my Palm-leaf marshmallow?

To fertilize a Palm-leaf marshmallow plant, the most common method is to apply granular or pellet fertilizer to the soil around the plant. Remember to fertilize when the plant is transitioning from its winter dormant phase to active growth, typically in early spring when shoots are emerging from the soil. If you prefer using liquid fertilizer, dilute it with water before applying. It's important to moisten the soil before, during, and after applying fertilizer, regardless of the type you choose.

🪴 Pot & Repot
✂️ Pruning

The palm-leaf marshmallow is characterized by its tall growth and lobed leaves. To maintain its health and appearance, it's best to prune the plant from early to late spring. During pruning, remove any dead wood, thin out overcrowded stems, and shape the plant to improve air circulation. These steps help rejuvenate the plant, enhance blooming, reduce pest issues, and improve its overall health and visual appeal.

🌿 Propagating
🐛 Diseases & pets
☠️ Toxicity

Characteristics

Plant Type
Herb
Life Cycle
Perennial
Genus
Althaea
Family
Malvaceae
Hardiness Zone
4-8
Mature Height
0.4 m to 2.13 m
Mature Spread
1.52 m
Leaf Color
Green, Blue
Leaf Type
Deciduous
Flower Color
Pink
Flower Size
3.05 cm to 5.08 cm
Bloom Time
Summer
Planting Time
Spring
Harvest Time
Late summer, Early fall, Mid fall
Native Area
Tajikistan, Turkey, Slovakia, Montenegro, Bulgaria, Pakistan, Armenia, Greece, Slovenia, Croatia, Ukraine, Lebanon, Uzbekistan, Russia, Serbia, Afghanistan, Iraq, Syria, Hungary, Kyrgyzstan, Kazakhstan, Italy, Spain, France, Iran, Albania, Azerbaijan, Algeria, Romania, Turkmenistan, Portugal

Tags (7)

Common Names (5)

en Palm-leaf-marshmallow
en Hemp-leaf-marshmallow
en Palm-leaf marshmallow
en Palmleaf Marshmallow
en Hemp-leaved marshmallow