Rough-fruit amaranth (Amaranthus tuberculatus)

Also known as: Tall pigweed, Roughfruit waterhemp

Amaranthus tuberculatus, also known as roughfruit amaranth, rough-fruited water-hemp, or tall waterhemp, is a flowering plant species. It is a summer annual broadleaf that can germinate over an extended period. This plant is recognized as a weed in 40 out of the 50 U.S. states.

In This Article

Care Tips Water Sunlight Temperature Soil Fertilize Prune Propagation Repotting

Attributes of Rough-fruit amaranth

Lifespan

Annual

Plant Type

Herb

Plant Height

1.67 to 6 feet

Spread

Not typically applicable as it is an herbaceous plant

Leaf Color

Various shades of green

Flower Size

Small, not typically measured

Flower Color

White Yellow Green

Images of Rough-fruit amaranth

Quickly Identify Rough-fruit amaranth

Waterhemp can be identified by its narrow, elongated leaves and the absence of hairs on the stem. It typically grows in dense clusters. The seeds are small, shiny, and dark, located in spiky flowers.

Scientific Classification of Rough-fruit amaranth

Phylum

Vascular plants

Class

Dicotyledons

Order

Caryophyllales

Family

Amaranth

Genus

Amaranths

Species

Rough-fruit amaranth

Planting and Growing of Rough-fruit amaranth

Care Difficulty

Easy

Watering Schedule

Every 4 days

Sunlight Requirements

Full sun

Sunshine Duration

6-10 hours

Ideal Temperature

65-85℉

Soil Type

Potting Mix, Peat Mix

Soil pH

6.5-7.5

Fertilizer Type

Balanced

Pruning Season

Spring, Summer

Pruning Area

Branches, Leaves

Pruning Frequency

2 times a year

Repotting Season

Spring

Pot Type

Plastic, Ceramic

How to Water Rough-fruit amaranth?

Amaranthus tuberculatus requires a consistent watering routine to thrive. Aim to provide about 250 milliliters of water per session, ensuring the soil is thoroughly moistened without waterlogging. The plant prefers its soil to be moist but not overly saturated, so adjust the volume based on existing soil moisture and environmental conditions.

What are the symptoms of an underwatered Rough-fruit amaranth? ›

What should I do if my Rough-fruit amaranth is not getting enough water? ›

What are the symptoms of an overwatered Rough-fruit amaranth? ›

How to save an overwatered Rough-fruit amaranth? ›

What Are the Sunlight Requirements for Rough-fruit amaranth?

Sunlight Requirements: Full sun, Partial sun

Duration of light: 6 to 8 hours daily

This plant benefits most from full to partial sun, with at least 6 to 8 hours of exposure daily, promoting healthy growth and vibrant foliage.

What is the best location for light exposure? ›

How can insufficient light affect this plant? ›

What measures can be taken to enhance light absorption? ›

What are the benefits of ideal light exposure? ›

More About Sunlight Requirements Techniques→

What Is the Ideal Temperature Range for Rough-fruit amaranth?

Ideal Temperature: 65 ~ 85℉

Maintaining the ideal temperature range of 65°F to 85°F is crucial for the optimal growth of Amaranthus tuberculatus. Within this range, the plant can efficiently carry out photosynthesis, leading to healthy growth and development.

What Soil is Best for Rough-fruit amaranth?

Soil type: Sandy soil, Loam, Sandy loam

Soil PH: 6.5 ~ 7.5

Amaranthus tuberculatus thrives in well-draining soil, which ensures that roots do not become waterlogged, preventing root rot and allowing for healthier plant development, especially in variable climates. This plant benefits from nutrient-rich soil that provides essential minerals. Such soil supports vigorous growth and increases the plant's resilience against pests and diseases, providing an optimal growth environment. A moderate level of organic matter in the soil helps improve its fertility, structure, and moisture retention, essential for maintaining the plant's growth cycle and resilience against environmental stress.

How to Fertilize Rough-fruit amaranth?

Fertilizer type: Balanced

The recommended fertilizer amount for Amaranthus tuberculatus varies depending on soil quality and plant size. Usually, a balanced liquid fertilizer with an NPK ratio of 10-10-10 can be applied at 1 tablespoon per gallon of water. For slow-release fertilizers, use about 2 pounds per 100 square feet.

How to Prune Rough-fruit amaranth?

Pruning Time: Spring, Summer, Autumn

Begin by assessing the structure of the Amaranthus tuberculatus. Look for the main stems and identify any overgrown areas. Use shears to cut back stems to the desired size, making cuts just above a leaf node to encourage new growth. Remove any crossing branches to enhance air circulation within the plant. For optimal growth, time your cuts during early morning or late afternoon to avoid the harsh midday sun which can stress the plant. Prune lightly during the growing season and more thoroughly at the end of the summer to prepare the plant for dormancy in autumn. More About Pruning Techniques→

How to Propagate Rough-fruit amaranth plant?

Propagate Time: Spring, Early summer

Collect seeds from mature Amaranthus tuberculatus plants. Ensure they are fully ripened and dry them out before storage to prevent mold and ensure germination viability.

The seeds should be lightly pressed into the potting mix in the seed tray. Avoid covering the seeds with too much soil, as they need light to germinate.

Keep the soil consistently moist but not waterlogged. Covering the tray with a plastic dome can help maintain moisture and warmth, facilitating optimal germination conditions.

More About Propagating Techniques→

How to Repot Rough-fruit amaranth plant?

Repotting frequency: Every 1-2 years

Amaranthus tuberculatus should be repotted when you notice that roots start to encircle the pot or protrude from the drainage holes. Another signal for repotting is when soil dries out rapidly, indicating that the plant may be root-bound. Ideally, repot during its active growth periods in spring or early summer to minimize stress.

Select a pot that is 2-3 inches larger in diameter than the current one to give the roots space to grow. Ensure it has drainage holes to prevent waterlogging and root rot. A slightly heavy pot can be beneficial to provide stability for the plant as it grows taller.

Opt for well-draining potting soil enriched with organic matter. This type of soil not only retains necessary nutrients but also prevents water stagnation, helping to keep roots healthy and promoting vigorous growth.