brittle waternymph
Najas minor · Najadaceae
brittle waternymph (Najas minor) is a annual herbaceous plant in the Najadaceae family. It is introduced to North America rather than native. USDA records it as hardy in zone 11 and warmer, down to about 47°F.
⚠ Invasive or noxious status. USDA lists this plant with an invasive or noxious weed status somewhere in its range. Check your state's noxious weed list before planting it — in some states it is illegal to sell or plant.
Both flags are quoted from USDA PLANTS, not inferred.
At a glance
| Type | forb-herb USDA |
|---|---|
| Lifecycle | annual USDA |
| Native status | introduced USDA |
| Mature height | 2 ft USDA |
| Light | part-shade USDA |
| Water need | high USDA |
| Growth rate | rapid USDA |
| Soil pH | 6.3–7.2 USDA |
| Bloom | August–September USDA |
| Flower color | Green USDA |
| Hardiness zones | 11 and warmer USDA |
| Guild layer | herb-layer Derived |
| Nursery availability | No Known Source USDA |
USDA quoted from the USDA PLANTS database · Derived computed by a fixed rule from those columns. No value on this page is estimated.
Growing conditions
It grows in partial shade. USDA rates it as having needs consistently moist ground. Its drought tolerance is rated none — it needs reliable moisture. It tolerates saturated, poorly drained ground well (USDA rates its anaerobic tolerance high). It is recorded on soils from pH 6.3 to 7.2 — a broad range that spans acidic through mildly alkaline ground. Its cold limit is zone 11.
Size and growth
At maturity it reaches about 2 ft, making it about knee height. It grows quickly.
Bloom period
USDA records a bloom period of August through September. Flowers are green.
A flowering date, not a pollinator rating.
Foliage, flower and season
Summer foliage is green, fine in texture. Its flowers are not conspicuous — a plant for form and foliage. Its active growth period is spring and summer.
What the site needs to provide
Fertility requirement: medium.
Propagating it
Sprigs is the only propagation method USDA lists. Its seed spreads at a moderate rate. It spreads vegetatively at a slow rate.
Resilience and wildlife
Its fire tolerance is rated high. Its growth form is recorded as colonizing.
Role in a guild
Herb layer. In a layered planting this is the herbaceous middle — perennials and grasses that fill the space between ground cover and shrubs. The layer is derived by a fixed rule from growth habit and mature height.
Tags
Related plants
Others in Najas
- nodding waternymph Najas flexilis
- southern waternymph Najas guadalupensis
Similar role and hardiness
- desert wheatgrass Agropyron desertorum
- nodding beggartick Bidens cernua
- purplestem beggarticks Bidens connata
- devil's beggartick Bidens frondosa
- proso millet Panicum miliaceum
Where this data comes from
Every value on this page comes from the USDA PLANTS database record for symbol NAMI, or is computed from those values by a fixed rule. Nothing here is estimated or model-generated. Where USDA publishes no value, this page omits the claim rather than filling the gap.
- Quoted from USDA PLANTS: active growth period, Bloom, Bloom end, cold stratification, Drought tolerance, fall conspicuous, fertility requirement, fire tolerance, Flower color, flower conspicuous, foliage color, foliage porosity winter, foliage texture, fruit conspicuous, growth form, Growth rate, Hardiness zones, Invasive status, Lifecycle, Light, Mature height, Minimum temperature, Native status, Nitrogen fixation, Nursery availability, propagation, resprout ability, seed spread rate, Soil pH, Soil pH (upper), Tolerance of wet soil, Toxicity, Type, vegetative spread rate, Water need.
- Derived by a fixed rule from those columns: Guild layer.
Read our full data sources and methodology.
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