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Giant Ragweed in the GardenTags plant encyclopedia

Ambrosia Trifida

 

Giant Ragweed

A very invasive, fast growing annual herb. It overcrowds crops, and grows faster than other plants, making it highly competitive. It is known as a noxious weed, and can be destructive to native and crop plants. It produces pollen that can cause breathing problems in susceptible people.n

Contributed by @brimbporter

 
plant Features
  • Giant Ragweed likes full sun to partial shade

    Full sun to partial shade

  • Giant Ragweed likes occasional watering

    Occasional watering

  • Giant Ragweed is full frost hardy: 5f (-15°c)

    Full Frost Hardy: 5F (-15°C)

  • Giant Ragweed likes all soil conditions

    All soil conditions

 
plant information

Common name

Giant Ragweed

Latin name

Ambrosia Trifida

type

Annual

family

Asteraceae

ph

5.5 - 8.5 Acid - Neutral

  • Light

    Giant Ragweed likes full sun to partial shade

    Full sun to partial shade

  • Frost

    Giant Ragweed is full frost hardy: 5f (-15°c)

    Full Frost Hardy: 5F (-15°C)

  • Soil

    Giant Ragweed likes all soil conditions

    All soil conditions

  • Water

    Giant Ragweed likes occasional watering

    Occasional watering

Plant & bloom calendar

  •  
    Best time to plant
  •  
    When the plant will bloom

full grown dimensions

The size of a fully grown Giant Ragweed is 1.50meters x 2.00meters 1.50 M 2.00 M

Ambrosia Trifida

A very invasive, fast growing annual herb. It overcrowds crops, and grows faster than other plants, making it highly competitive. It is known as a noxious weed, and can be destructive to native and crop plants. It produces pollen that can cause breathing problems in susceptible people.n


Flowering

From Mid Summer TO Late Summer

Spikes of small greenish flowers, that turn yellowish-green then brown, appear at the end of the stems in Summer, the male flowers producing the pollen that is easily carried on the wind, and can cause breathing problems in susceptible people. The pollen is usually released in late Summer or Autumn. Near the base of the central flowering spike, one or two small spikes may develop that are only half as long.

 

Planting

From Early Spring TO Mid Spring

This is an invasive plant that would not generally be wanted or planted. It is not fussy about the type of soil, but prefers full sun

 
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