Grewia occidentalis
Images by part: leaf (5) · flower (5) · fruit (1) · bark (2) · habit (3) · other (1)

Grewia occidentalis

Crossberry · Lavender starflower · Four-corners · Starflower

Tier 1 Difficulty: easy Water: low Light: full_sun
Water every
7 days
Temperature
20–37 °C
Soil pH
6–7
Hardiness
Zone 9–11
Click count
160
Observations
248

Description

Source: leafsnap

Grewia occidentalis, commonly known as Crossberry or Four-cornered Berry, is a small to medium-sized shrub belonging to the Malvaceae family. Native to southern Africa, this plant thrives in a variety of habitats, including forests, savannas, and grasslands. The shrub features a multi-stemmed growth habit with an upright form, reaching heights of up to 3 meters. Its leaves are simple, alternate, and oval-shaped with serrated edges. The flowers, which vary in color from white to pinkish-purple, are small and have five petals. The fruit of Grewia occidentalis is a four-lobed berry that transitions from greenish-yellow when unripe to reddish-brown when mature. It has a sweet taste and is edible for both humans and animals. Traditionally, Grewia occidentalis has been used for its medicinal properties, particularly for treating diarrhea, dysentery, coughs, colds, fever, headaches, and other ailments, owing to its anti-inflammatory properties. Overall, Grewia occidentalis plays a significant role in southern Africa's ecosystem. It provides food for animals and holds medicinal value for humans, underscoring its ecological and cultural importance.

Care Guide

💧 Water Every 7 days

Crossberry thrives in semi-arid regions, where it benefits from infrequent but deep watering every 1 to 2 weeks. It's important to let the soil dry out between watering sessions. Typically grown outdoors, Crossberry requires full sun and displays impressive drought tolerance. As an evergreen plant, it efficiently maintains hydration across a range of climates.

Suggested frequency: Every 7 days
FAQ
How should I water my Crossberry plant?

Your Crossberry plant is not picky about how you water it. You can use common watering tools like watering cans, hoses, or cups. When watering the plant, it's important to apply the water directly to the soil and make sure all areas of the soil are moistened evenly to provide water to the entire root system. It's recommended to use filtered water instead of tap water, as tap water may contain harmful particles. Additionally, using water at or slightly above room temperature is beneficial, as extremely cold or hot water can shock the plant. However, the Crossberry plant usually responds well to any type of water you give it.

What do I do if I give my Crossberry plant too much or too little water?

Outdoor plants, particularly newly planted plants or seedlings, are prone to lack of watering. It's important to remember to water them consistently for the first few months while they are still small or newly planted. Once their roots are established, Crossberry plants can rely on rain for most of their water needs. When planting Crossberry in pots, overwatering is more likely. If you accidentally overwater your Crossberry, you should take immediate action to fix the situation. Firstly, stop watering the plant to minimize the negative effects. Next, remove the Crossberry from its pot and inspect the roots. If there are no signs of root rot, you can return the plant to its container. However, if root rot is present, trim away the affected roots and consider applying a fungicide to prevent further damage. Lastly, repot the Crossberry in well-draining soil. In the case of underwatering, simply increase the frequency of watering. Underwatering is usually easy to correct, as the plant's leaves will droop, dry out, and may fall off. After sufficient watering, the leaves will quickly regain their fullness. It's important to adjust your watering schedule as soon as you notice underwatering occurring.

How frequently should I water my Crossberry plant?

Most outdoor plants can grow naturally with rainfall, but if there is a lack of rainfall in your area, you should water your plants every 2 weeks during the spring and fall. In the summer, more frequent watering is required, while in the winter, when growth is slower, you can water less frequently. In fact, during the winter, you may not need to water your plants at all. However, if your Crossberry is young or newly planted, it needs more regular watering to establish and grow into adaptable and drought-tolerant plants. For potted Crossberry plants, there are two main ways to determine the watering frequency. The first way is to stick to a set watering schedule, such as once every week or once every other week. However, this may not always work well as it doesn't consider the specific conditions of your Crossberry's environment. Watering frequency can also change depending on the season. For example, during summer, when the plant's water needs are highest, a predetermined schedule may not be sufficient. An alternative approach is to water based on soil moisture. It is generally best to wait until the top two to four inches of soil (about ⅓ to ½ depth of the pot) have completely dried out before watering again.

How much water does my Crossberry plant require?

When watering your Crossberry plant, you might be surprised to learn that it doesn't always require a large amount of water. Instead, if only a few inches of soil have dried since the last watering, providing approximately five to ten ounces of water each time will promote healthy growth. You can also gauge the amount of water needed based on the moisture level of the soil. Take note of how many inches of soil have dried between waterings. To ensure your Crossberry receives enough moisture, water it until all the dry layers of soil have been moistened since the last watering. If over half of the soil has dried, you should consider giving more water than usual. In such cases, continue watering until you see excess water draining from the pot's holes. If your Crossberry is planted outdoors in an area that receives ample rainfall, it may not require additional watering. For young or newly established Crossberry plants, ensure they receive 1-2 inches of rain per week. As the plant grows and establishes, it can rely solely on rainwater, except during very hot weather or extended periods without rainfall for 2-3 weeks. In such cases, it's advisable to give your Crossberry a thorough watering to prevent stress.

How do I know if I'm giving my Crossberry plant enough water?

Overwatering is a common issue for Crossberry plants, and there are clear signs to watch out for. When a Crossberry is overwatered, its leaves will turn yellow and it may shed some leaves. Additionally, overwatering can cause the plant's overall structure to shrink and can lead to root rot. On the other hand, if a Crossberry is underwatered, it will also begin to droop. Its leaves may become brown and brittle to the touch. Regardless of whether you notice signs of overwatering or underwatering, it is important to take action and restore the health of your Crossberry plant.

☀️ Light Full sun

Crossberry requires ample sunlight for optimal growth, similar to its native habitat. Throughout its growth stages, abundant but mild light encourages balanced development. However, prolonged periods of intense sunlight can be damaging, and too little light likewise inhibits growth and vigor.

Ideal: Full sun
FAQ
What are the sunlight requirements for Crossberry plants?

Crossberry plants enjoy full sun, which is above 6 hours of sunlight daily, but can also thrive in partial sun, receiving about 3-6 hours of sunlight. It's crucial to observe how sunlight moves through your garden to ensure that you place your plants in spots that offer the right balance of light and shade, contributing to their overall happiness and growth.

How important is sunlight for the growth of Crossberry plants?

Sunlight plays a pivotal role in the growth and development of Crossberry plants. These plants crave extensive solar exposure for optimal growth, mirroring their native habitat conditions. At different growth stages, ample yet gentle sunlight encourages a well-rounded development. Too much intense sunlight or insufficient light can negatively impact the plant's growth, vitality, and ability to produce flowers or fruit.

Can artificial lighting be used for Crossberry plants? How?

Yes, artificial lighting can be a vital solution for Crossberry plants, especially when natural sunlight is insufficient, such as during winter or in less sunny indoor spaces. Adequate lighting promotes faster and healthier growth. LED lights are preferred for their ability to provide specific wavelengths of light needed by plants. Full sun plants require 30-50W/sq ft, partial sun plants need 20-30W/sq ft, and full shade plants 10-20W/sq ft of artificial light. The light source should be placed 12-36 inches above the plant, mimicking natural sunlight for about 8-12 hours per day.

What are some common symptoms of light deficiency in Crossberry plants?

Symptoms of light deficiency in Crossberry plants include smaller new leaves, leggy or sparse growth, faster leaf drop, slower or no new growth, lighter-colored new leaves, chlorosis (leaves turning yellow), sunscald (damage due to intense sunlight), leaf curling, wilting, and leaf scorching. These signs indicate the plant is not receiving adequate sunlight, affecting its health and development.

How can I address light deficiency symptoms in Crossberry plants?

Addressing light deficiency in Crossberry plants involves several strategies. Indoor plants can be gradually moved to sunnier locations to achieve at least 6 hours of direct sunlight daily or supplemented with artificial light for at least 8 hours daily. Outdoor and ground-planted Crossberries should be moved to spots with better sunlight exposure gradually to prevent sunburn. It's also beneficial to minimize obstructions by pruning trees or relocating plants to sunnier areas. However, parts of the plant that have been severely affected by light deficiency may not recover entirely, but new growth should be healthier with improved light conditions.

🌡️ Temperature 20–37.8°C

Crossberry originates from temperate regions and is adapted to a preferred temperature range of 68 to 100 °F (20 to 38 ℃). For optimal growth, keep the temperature within this range, particularly during seasonal transitions.

Ideal temperature: 20–37.8°C
FAQ
What is the native climate for Crossberry plants?

Crossberry, also known as Grewia occidentalis, is native to regions that have a temperate climate. It is well-suited for temperatures ranging from 68 to 100 °F (20 to 38 °C). To ensure optimal growth, maintaining this temperature range is crucial, especially during the changing seasons. Crossberry plants are extremely heat-loving, and exposure to cold temperatures can be harmful to them.

What should I do with my Crossberry plant in autumn and winter to protect it from cold?

In autumn, it is advisable to bring Crossberry plants indoors if they have been grown outside, placing them near a bright window to ensure they continue to receive sufficient light. However, they should be kept at a safe distance from heaters to avoid damage. During winter, maintaining temperatures above 20°C is beneficial for the plant’s growth, as temperatures approaching 0°C or lower can be detrimental. Keeping the plant in a warm environment is key to protecting it from cold-related harm.

How does low temperature affect Crossberry plants, and what are the solutions?

Crossberry plants prefer warm temperatures and do not tolerate low temperatures well, thriving best when the temperature is above 20°C. During winter, they should be kept in conditions above 0°C. Exposure to temperatures below -5°C can cause the leaves to lighten in color, and if the plant experiences frost damage, the leaves may eventually turn brown or black. Symptoms such as wilting and drooping can also occur. To remedy frost damage, you should trim off the frost-damaged parts and move the plant to a warmer indoor spot, preferably near a south-facing window for adequate sunlight. Avoid placing the plant near heaters or air conditioning vents as this can cause the air around the plant to become excessively dry.

What should I do if my Crossberry plant experiences high temperature?

During the summer, it is important to keep Crossberry plants in conditions below 38°C to avoid heat stress. If temperatures exceed 43°C, the plant’s leaves may become lighter in color and it becomes more susceptible to sunburn. To mitigate this, trim away the sunburned and dried-up parts of the plant and move it to a location that is shielded from the midday and afternoon sun. Watering the plant in the morning and evening can also help keep the soil moist and reduce stress from high temperatures.

💨 Humidity normal (40-60%)

This plant will thrive in moderate humidity, which is probably the level in your home. However, misting it a few times a week can be very beneficial. Make sure the room has good ventilation.

Humidity: normal (40-60%)
🪴 Soil 6-7
Soil pH: 6-7
🌱 Fertilizer

The best time to fertilize a Crossberry is in early spring when it comes out of dormancy. This promotes overall growth and supports flower development. Fertilization improves the foliage, stems, and branches, and encourages large, vibrant, long-lasting flowers. It also helps move nutrients from the roots to the flowers and enhances the plant's health and resistance to disease.

FAQ
Why should I put fertilizer on my Crossberry plant?

Fertilization plays a crucial role in the overall health and well-being of a Crossberry plant. By providing the necessary energy and nutrients, it promotes the growth of healthy foliage, sturdy stems, and branches. One of the main benefits of fertilization is its impact on the flowers of the Crossberry, which are highly valued by gardeners. The right fertilizer results in larger, more vibrant, and longer-lasting flowers. This is because it facilitates the transfer of fuel from the plant's roots to its flowers through the stems. Additionally, proper fertilization helps maintain the plant's overall health, enhancing its ability to resist diseases.

When should I fertilize my Crossberry plant?

The best time to fertilize a Crossberry plant is in early spring when it is coming out of dormancy and getting ready to bloom. This will provide the plant with energy for growth and flower development. However, it's also beneficial to fertilize it again in the fall, although a smaller amount is sufficient. Some gardeners prefer to fertilize when planting, but it's not always necessary.

When is the best time to not put fertilizer on my Crossberry plant?

During the winter, Crossberries, like many other plants, do not require fertilization. They are in a dormant phase and do not need much energy from the soil for new growth. Fertilizing them during winter increases the risk of overfertilization. The best time to feed a Crossberry is in early spring and fall. Therefore, for most of the spring and summer, fertilizer is not needed. Additionally, it is advisable to refrain from feeding if the plant is subjected to excessively hot or dry conditions.

What kind of fertilizer should I use for my Crossberry plant?

Generally, using a general-purpose fertilizer with equal amounts of nitrogen, phosphorus, and potassium is acceptable. However, Crossberry plants typically thrive with a specific fertilizer. The key nutrients for Crossberries are nitrogen and phosphorus, so the fertilizer you choose should have higher amounts of these compared to potassium. A fertilizer with an N-P-K ratio of 10-10-8 or something similar should be suitable. Additionally, it is also beneficial to use organic materials like compost for at least one of your yearly feedings. If you opt for fertilizer, granular fertilizer is commonly used for Crossberries.

How do I make my Crossberry plant grow better?

Fertilizing your Crossberry plant is an easy task that any gardener, regardless of experience, can do. To use granular fertilizer, simply sprinkle it onto the soil after moistening it with water. Another option is to improve the soil by adding organic material like compost or manure. For this method, place the material on top of the soil and gently work it into the first few inches using a hand rake, being careful not to disturb the roots.

🪴 Pot & Repot 2-3 years

Repot crossberry every 2 to 3 years during the spring. Use a container that is 2 to 3 inches wider than the root ball. After repotting, place it in indirect light and keep the soil moist to help it recover and encourage blooming.

Suggested frequency: 2-3 years
✂️ Pruning

The evergreen shrub known as the crossberry benefits greatly from regular pruning during its dormant period, which occurs from early to late winter. To enhance airflow, flowering, and overall plant health, remove any dead or crossing branches. Be sure to use clean, sharp tools to minimize damage and reduce the risk of disease.

🌿 Propagating
🐛 Diseases & pets
☠️ Toxicity

Characteristics

Plant Type
Tree, Shrub
Life Cycle
Perennial
Genus
Grewia
Family
Malvaceae
Hardiness Zone
9-11
Mature Height
3.96 m
Mature Spread
2.44 m
Leaf Color
Green
Leaf Type
Evergreen
Flower Color
Lavender
Flower Size
2.54 cm to 5.08 cm
Bloom Time
Late spring, Summer, Early fall
Planting Time
Spring
Harvest Time
Late summer, Fall
Native Area
Saudi Arabia, Lesotho, Mozambique, South Africa, Eswatini, Zimbabwe

Tags (8)

Common Names (4)

en Crossberry
en Lavender starflower
en Four-corners
en Starflower