Mirabilis nyctaginea
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Mirabilis nyctaginea

Heart-leaf four-o'clock · Heart-leaf umbrella-wort · Wild four-o'clock · Heartleaf four o'clock · Heart-leaved Four O'clock

Tier 1 Difficulty: medium Water: low Light: full_sun
0
Soil pH
6–7
Hardiness
Zone 3–11
Click count
166
Observations
218

Description

Source: leafsnap

Mirabilis nyctaginea is a species of flowering plant in the four o'clock family known by several common names, including wild four o'clock, heartleaf four o'clock, and heartleaf umbrella wort. Four-o'-clock is native to the central section of North America, and it occurs elsewhere as an introduced species, including parts of Europe. Its exact native range is obscure, and it is often weedy throughout its range, spreading into disturbed habitat easily. Four-o'-clock is a hairy to hairless perennial herb growing erect to over a meter in maximum height. The leaves are oppositely arranged mainly on the lower two thirds of the plant below the upper forkings of the stem. Each thin green leaf has an oval or heart-shaped blade up to 10 centimeters long. The flowers occur in leaf axils on the upper branches. A cluster of 3 to 5 flowers blooms in a bell-shaped involucre of five partly fused bracts. Each five-lobed, funnel-shaped flower is about a centimeter wide and magenta or pink to nearly white in color. The flowers open for only a few hours and drop, leaving the shaggy-haired developing fruits in the drying, papery cup of bracts. The root is a thick, fleshy taproot. Four-o'-clock is host to the larvae (caterpillars) of several micromoths: Embola ionis is a stem borer, Neoheliodines cliffordi and N. nyctaginella are leaf skeletonizers, and Aetole tripunctella is a leaf miner.

🌳 Among Native American peoples, the wild four o'clock played a role in various cultural rituals and practices, for example being used as a source of dyes and for ceremonial ornamentation. The plant's pigment-producing ability was employed to color textiles and objects, indicating an area of exploitation potential beyond its conventional uses.

🎭 Comfort in the essential

Care Guide

💧 Water

Wild four o'clock plants thrive in temperate regions where there is moderate moisture. They prefer soil that is consistently moist but not waterlogged, which can be achieved with weekly watering. These plants are adaptable to different rainfall patterns, making them well-suited for gardens in climates with predictable seasonal rains.

FAQ
How should I water my Wild four o'clock plant?

To ensure the well-being of the Wild four o'clock plant, it's best to water it using filtered water. This is important because tap water may contain harmful particles that can affect its health. Moreover, it's necessary to use water at room temperature or slightly warmer. This is because the Wild four o'clock plant is accustomed to warm environments, and cold water may shock its system. Additionally, overhead watering should be avoided as it can cause issues with the foliage. Instead, a better approach is to apply the filtered room temperature water directly to the soil until it is completely soaked. Doing so benefits the plant by providing moisture to its roots, aiding in their spread through the soil and enabling nutrient collection.

What should I do if I give my Wild four o'clock plant too much water or too little water?

Overwatering is a common issue that can harm your Wild four o'clock plant. It causes wilting and yellowing of the stems and leaves, and can lead to diseases like root rot, mold, and mildew. Underwatering is less common because this plant can tolerate drought, but it can still happen. In this case, the leaves become brittle and brown. It's important to notice the signs of overwatering early on. Diseases like root rot can't be fixed if you wait too long. If you see these signs, reduce your watering schedule and check the quality of the soil. If it doesn't drain well, replace it with a loose, well-draining potting mix. If you notice signs of underwatering, simply water more regularly until the signs disappear.

How often should I give water to my Wild four o'clock plant?

If you have a potted Wild four o'clock plant, you can check if it needs water by inserting your finger into the soil. If the top two to three inches of soil feel dry, it's time to water it. For outdoor Wild four o'clock plants, the same method applies. If the top few inches of soil are dry, it needs watering. Normally, watering once a week is sufficient during spring and early fall. However, during extremely hot weather, you may need to water twice or more per week. It's worth noting that mature and well-established Wild four o'clock plants can tolerate drought well.

How much water does my Wild four o'clock plant need?

To properly water your Wild four o'clock plant, don't hold back on the amount of water you give. Wait until the top two to three inches of soil have dried out, then give the plant a good, thorough watering. Make sure to water the soil completely, enough so that excess water drains out of the pot. If you don't see water draining from the pot, you may not be giving enough water. However, be careful not to let water accumulate inside the soil, as this can harm the plant. On the other hand, if water doesn't drain out of the pot, it may be a sign of poorly draining soil, which is bad for the plant's health. If the plant is outside, one inch of rainfall per week should be enough.

How do I water my Wild four o'clock plant as it grows?

The water needs of the Wild four o'clock can vary depending on its growth stages. In the early years or when you move it to a new location, it requires more water. During these stages, the plant focuses on growing new roots, which need extra moisture to support future growth. However, as the plant matures, its water needs reduce significantly. Additionally, during the blooming period, the Wild four o'clock requires more water because the development of flowers uses up a significant amount of moisture.

☀️ Light Full sun

Wild four o'clock prefers being in areas with plentiful sunlight throughout the day. In its native habitat it performs best where it gets the sun for most of the day. Still, it can tolerate locations with somewhat reduced sunlight. Excessive shade can cause the plant to perform poorly, while too much sun can result in leaf scorching.

Ideal: Full sun
FAQ
What are the sunlight requirements for Wild four o'clock?

Wild four o'clock (Mirabilis nyctaginea) thrives best with ample sunlight exposure throughout the day. It requires full sun, which means it needs to be in a spot that receives more than 6 hours of direct sunlight daily. However, it can also grow in partial sun locations, where it receives about 3-6 hours of sunlight daily. Being adaptable, it manages slight variations in light but perfoms poorly in excessive shade, resulting in underperformance, or in too much direct light, which might cause leaf scorching.

How can artificial lighting be used for indoor plants?

Indoor plants, including Wild four o'clock, may require artificial lighting to achieve optimal growth, especially in conditions where natural sunlight is insufficient. LED lights are recommended as they can provide specific wavelengths needed for plant growth. For plants needing full sun, 30-50 watts per square foot of artificial light is needed; partial sun plants require 20-30 watts per square foot; and full shade plants need 10-20 watts per square foot. The light source should be placed 12-36 inches above the plant and kept on for 8-12 hours a day to mimic natural daylight hours.

What are some common symptoms of inadequate lighting for Wild four o'clock?

Symptoms of inadequate light in Wild four o'clock include smaller new leaves, leggy or sparse growth, premature leaf drop, delayed or halted new growth, lighter-colored new leaves, and various signs of distress like chlorosis, sunscald, leaf curling, wilting, and leaf scorching. These signs reflect the plant's stress due to either insufficient or excessive sunlight exposure, affecting its health and growth.

How can light exposure be optimized for Wild four o'clock?

To optimize light exposure for Wild four o'clock, gradually move indoor plants to sunnier locations to receive at least 6 hours of direct sunlight daily, utilizing south-facing windows for maximum exposure. Artificial light can supplement natural sunlight, especially for larger or less mobile plants. Outdoors, plants should be gradually moved to sunnier spots to avoid shock. If necessary, prune or remove obstacles blocking sunlight. For small plants, transplantation might be a viable option during their dormant period to ensure adequate light intake. It's crucial to ensure that adjustments to light exposure are made gradually to prevent plant stress.

🌡️ Temperature 0–37.8°C

The wild four o'clock is native to North America and occurs in a temperature range of 0 to 38 ℃ (32 to 100 ℉). It prefers warm daytime temperatures and cooler nighttime temperatures. In the summer it may benefit from partial shade to prevent heat stress.

Ideal temperature: 0–37.8°C
FAQ
What is the native region and optimal temperature range for the wild four o'clock?

The wild four o'clock, known botanically as Mirabilis nyctaginea, is native to North America. It thrives in a variety of temperatures ranging from 0 to 38 °C (32 to 100 °F). This plant prefers warm daytime temperatures with cooler temperatures at night. During summer months, partial shade can be beneficial to prevent heat stress. Its strong cold resistance typically obviates the need for special frost protection measures in winter, though protection is advised if temperatures drop below its growth limit.

How should the wild four o'clock be cared for in winter?

Despite its strong cold resistance, if winter temperatures are expected to fall below the plant's growth limit, it's important to protect the wild four o'clock from the cold. This can be done by covering the plant with soil or straw. Additionally, before the first freeze of the autumn, it's recommended to water the plant abundantly so the soil remains moist going into its frozen state, helping prevent drought and water scarcity during winter and early spring.

What are the symptoms of low temperature exposure and solutions for the wild four o'clock?

The wild four o'clock is cold-tolerant and performs best when the temperature remains above its minimum suitable growth temperature. During winter, maintaining a temperature above its minimum tolerable growth level is ideal. Exposure to temperatures below its growth limit may not show immediate changes but can lead to decreased or absent sprouting in spring. If sprouting is affected, removing the non-sprouting parts in spring is recommended.

What are the high temperature concerns and care solutions for the wild four o'clock?

In summer, it's crucial to keep the wild four o'clock below its maximum suitable growth temperature. Exceeding its tolerable high temperature can cause the leaves to lighten in color, become prone to curling, suffer sunburn, and in severe cases, cause the plant to wilt and dry. To mitigate these issues, trim away sunburned and dried-up parts, relocate the plant to a shaded area during peak sun or use shade cloth, and ensure the soil is kept moist by watering in the morning and evening.

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

Generally, a single fertilizer application in spring is adequate for Wild four o'clock, though repeated feedings can enhance growth. Fertilize every month to every six weeks. Feeding improves the leaves' appearance and function, helping maintain uniform color and a healthy texture. It also promotes root development and nutrient uptake, supporting the plant's long-term health.

FAQ
Why should I put plant food on my Wild four o'clock plant?

The Wild four o'clock relies on its leaves for structure, and fertilization is key to keeping these leaves looking great and functioning properly. Proper fertilization promotes consistent leaf color and a healthy texture. Additionally, fertilization benefits the plant below the surface by encouraging new root growth and maintaining existing roots. This not only improves the plant's current health but also enhances its ability to absorb nutrients from the soil in the long run.

When should I fertilize my Wild four o'clock?

If you grow your Wild four o'clock outdoors, it will send new growth in early spring. This signals the time to fertilize it. Generally, a single application of fertilizer in spring is sufficient. However, if you want to maximize growth, you can fertilize it multiple times during spring and early summer, about once every month to a month and a half.

When should I not put fertilizer on my Wild four o'clock plant?

During the late fall and winter, your Wild four o'clock will go into a dormant phase and stop growing. Therefore, it is important to avoid fertilizing it during this time. If you do choose to fertilize in the spring and summer, start reducing the amount of fertilizer as summer approaches and the growth rate slows down. It is always best to avoid fertilizing your Wild four o'clock during excessively hot weather or when the soil is unusually dry, as doing so can stress the plant and cause it to die prematurely.

What kind of plant food does my Wild four o'clock need?

Choosing the best fertilizer for a Wild four o'clock is actually quite simple. These plants do well with a general-purpose garden fertilizer that contains equal amounts of nitrogen, phosphorus, and potassium. Look for a fertilizer with a ratio of 10-10-10 or something similar, as it will work effectively. It's important to be cautious about fertilizers with high nitrogen content when unsure. In most cases, the ideal fertilizer for a Wild four o'clock will come in granular form. These fertilizers should be slow-release and easy to apply to the soil. It's also beneficial to supplement with organic soil amendments, such as compost, to nourish your Wild four o'clock.

How should I add fertilizer to my Wild four o'clock plant?

To ensure the health of your Wild four o'clock plant, wait until it starts to sprout in early spring. At this point, apply a slow-release fertilizer with a balanced formula to the soil around the base of the plant. You can repeat this process later in the season if desired. Remember to apply the fertilizer to the soil, not the plant itself. Sometimes, you may need to move some leaves aside to access the soil above the roots. Additionally, watering the plant before and after fertilizing is often beneficial.

🪴 Pot & Repot 2-3 years

When repotting Wild four o'clock, choose a pot 1-2 inches (2.5–5.1 cm) larger with ample drainage. Use a well-draining potting mix. Repot in spring or fall, making sure the root ball sits slightly lower than the rim of the flower pot. Water thoroughly after repotting and place it in a warm spot with indirect sunlight.

Suggested frequency: 2-3 years
✂️ Pruning

The wild four o'clock plant features heart-shaped leaves and vibrant flowers. To encourage strong growth and abundant blooming, it is important to prune it regularly from early to late spring. This involves trimming dead stems, maintaining the plant's shape, and improving air circulation to reduce the risk of disease. For more detailed pruning techniques and advice, consult horticultural resources.

🌿 Propagating
🐛 Diseases & pets
☠️ Toxicity

Characteristics

Plant Type
Herb
Life Cycle
Perennial
Genus
Mirabilis
Family
Nyctaginaceae
Hardiness Zone
3-11
Mature Height
91 cm
Mature Spread
49 cm
Leaf Color
Green
Leaf Type
Deciduous
Flower Color
Pink, White
Flower Size
1.02 cm
Bloom Time
Late spring, Early summer, Mid summer
Planting Time
Spring, Summer
Harvest Time
Summer
Native Area
Mexico

Tags (8)

Common Names (8)

en Heart-leaf four-o'clock
en Heart-leaf umbrella-wort
en Wild four-o'clock
en Heartleaf four o'clock
en Heart-leaved Four O'clock
en Heart-leaved four-o'clock
en Heart-leaved Umbrellawort
en Prairie Four-o'clock