If you’re wondering how tall Amaranth gets, I get you covered.
In this post, you will learn everything about Amaranth height, and find how tall different varieties of this plant get.
How Tall Does Amaranth Grow?
Most Amaranth varieties grow up to about 3 feet tall (90 cm). Some varieties can be as small as 1 ft (30 cm), and some might be bigger than average, for example, 8 ft (243 cm).
When it comes to Amaranth’s height, the most important factors determining its health are variety, water, light, temperature, and nutrients.
Learn more about different heights of varieties, and how to care for your Amaranth to grow properly.
How Tall Do Different Amaranth Varieties Grow?
| Amaranth Variety | Height |
| Amaranthus caudatus ‘Coral Fountain’ | 3-5 ft (90-150 cm) |
| Amaranthus caudatus ‘Dreadlocks’ | 2-4 ft (60-120 cm) |
| Amaranthus cruentus ‘Autumn’s Touch’ | 3.5-4 ft (100-120 cm) |
| Amaranthus cruentus ‘Copperhead’ | 4-5 ft (120-150 cm) |
| Amaranthus cruentus ‘Hopi Red Dye’ | 4-6 ft (120-180 cm) |
| Amaranthus cruentus ‘Hot Biscuits’ | 4 ft (120 cm) |
| Amaranthus hybridus ‘Opopeo’ | 5-7 ft (150-210 cm) |
| Amaranthus hypochondriacus ‘Green Thumb’ | 1-2 ft (30-60 cm) |
| Amaranthus hypochondriacus ‘Pygmy Torch’ | 1-2 ft (30-60 cm) |
| Amaranthus tricolor ‘Joseph’s Coat’ | 1.5-5 ft (45-152 cm) |
| Amaranthus cruentus ‘Red Spike’ | 3.2-5 ft (100-150 cm) |
| Amaranthus caudatus ‘Green Love Lies Bleeding’ | 3-8 ft (90-243 cm) |
| Amaranthus tricolor ‘Early Splendor’ | 2-5 ft (60-150 cm) |
| Amaranthus bicolor ‘Illumination’ | 2 ft (60 cm) |
| Amaranthus cruentus ‘Emerald Tassels’ | 2.5-5 ft (76-152 cm) |
| Amaranthus cruentus ‘Yellow Tricolor’ | 2-4 ft (60-120 cm) |
| Amaranthus caudatus ‘Coral Fountain’ | 4-5 ft (120-150 cm) |
| Amaranthus tricolor ‘Perfecta’ | 3-3.7 ft (90-115 cm) |
As you can see from the table, Amaranth can be as small as 1 ft (30 cm), or as big as 8 ft (243 cm).
How Fast Does Amaranth Grow?
Amaranth grows on average approximately 1 foot (30 cm) per month, or 3 inches per week (7.62 cm). Depending on the stage of development, the speed of growth will vary.
Keep in mind that these are the average numbers because each Amaranth variety reaches a different height. These are numbers for an Amaranth that gets 3 feet (91 cm tall).
Also, the growth speed of Amaranth will vary depending on the stage of growth. During germination or the seedling phase, the plant will grow slowly, like 1-2 inches (2.5-5 cm) per week.
However, when the Amaranth is creating buds and flowering, it typically grows much faster, and it will grow even more than 1 foot (30 cm) per month.
The typical lifespan of an Amaranth from planting to flowering is 3 months.
Related: How Long Does it Take to Grow Amaranth? (Solved)
How Long Does Amaranth Take to Reach Full Height?
Amaranth reaches its full size just before it dies, which is in about 3 months after planting.
However, some Amaranth varieties take longer to reach their full size. For example, Hybridus ‘Opopeo’ might reach its full size in more than 4 months.
When Amaranth is mature, it reaches its full size. A good indicator that Amaranth has just reached its full size is the grains. If you gently but briskly shake or rub the flower heads between your hands and see if the grains fall readily, it means that from now, Amaranth will be dying off, and won’t grow any bigger.
What Factors Affect Amaranth Height?
Variety
Variety is the most important thing that determines Amaranth’s height. Some varieties, like Pygmy Torch in many cases, might be as small as 1 ft (30 cm), and some might be even higher than 8 ft (243 cm), for example, Green Love Lies Bleeding.
Water
In Amaranth’s case, watering too much is more harmful than watering too little. The plant isn’t a water-lover. It just needs about 1 inch (16 ml) per week. Usually, rain does all the work for you. However, if you water your Amaranth too often, and too much, the plant will grow way smaller, as it can develop root rot or fungal disease.
Light
The more sunlight Amaranth receives, the taller it gets, as it converts light, water, and oxygen into energy to grow. Amaranth likes full sun, especially when the climate isn’t too hot. If you grow your Amaranth in hot weather, when the temperatures are often above 85 °F (29 °C), Amaranth might tolerate partial sun.
Temperature
Amaranth grows tallest when the temperature is between 70-85 °F (21-29 °C). The plant is native to Mexico, so these temperatures are perfect. If the temperature is lower, or higher than that, Amaranth tends to stunt its growth, and the crop quality might be lower.
Nutrients
Lack of adding nutrients will have a positive impact on your Amaranth. This plant doesn’t require any fertilization, and it grows tallest without any help. Fertilizing might be the problem because if the Amaranth gets too much nitrogen, it might hinder growth, flowering, and seed production.