Variety field guide
What to expect from Mammoth Grey Stripe
Mammoth Grey Stripe Sunflower seeds produce yellow bloom on 97–120 in upright/erect plants. Annual growth and Summer/Fall bloom make it useful for sunny borders, cut flowers, pollinator use, seed heads, and seed saving.
Read the complete product descriptionTraits, flavor, garden use, variety notes, and the full catalog record
Mammoth Grey Stripe Sunflower seeds produce yellow bloom on 97–120 in upright/erect plants. Annual growth and Summer/Fall bloom make it useful for sunny borders, cut flowers, pollinator use, seed heads, and seed saving.
About Mammoth Grey Stripe
Mammoth Grey Stripe is an annual sunflower with yellow color, 97–120 in mature height or spread, and an upright/erect habit. Harvest form or size: Flower or head form characteristic of Mammoth Grey Stripe; mature plant 97–120 in. Botanically it is Helianthus annuus. Maturity or first bloom: 80-89 Days; germination: 7-14 Days at 65–80 °F. Best for sunny borders, cut flowers, pollinator use, seed heads, and seed saving. Ornamental bloom and mature seed use depend on the named strain and harvest stage.
History and provenance
Sunflower, Helianthus annuus, originated in North America and was cultivated by Native peoples for food, oil, dye, and other uses before its spread around the world. Modern named garden strains emphasize differences in plant height, branching, ray color, head form, seed size, and days to bloom. Public records do not document a single breeder for every catalog name, so the named strain is retained without adding an unsupported release story. A complete public breeder or release record for the named Mammoth Grey Stripe strain has not been located. The cultivar name is retained, but no person, community, date, or place of origin is assigned without reliable documentation.
Growing facts
| Scientific name | Helianthus annuus |
|---|---|
| Life cycle | Annual |
| Maturity / first bloom | 80-89 Days |
| Germination | 7-14 Days at 65–80 °F |
| Seed depth | 1 in |
| Plant height / spread | 97–120 in |
| Growth habit | Upright/Erect |
| Spacing | 12 in between plants; 30 in between rows |
| Sunlight | Full sun |
| Soil | Loamy; pH 6.0–6.5 |
| Water | Moderate |
| Support | Stake |
Starting Mammoth Grey Stripe from seed
How to grow Mammoth Grey Stripe Sunflower
Botanical identity: Helianthus annuus. Life cycle: Annual.
Sow 1 in and use a seed-zone temperature near 65–80 °F. Expected emergence: 7-14 Days. Use clean seed-starting conditions, the listed depth and temperature, and steady moisture without saturation.
Plant during Late Spring. Space plants 12 in apart with 30 in between rows or planting bands.
Provide Full sun, moderate water, and loamy near pH 6.0–6.5. Support: Stake.
Garden performance and care
For a longer display of Mammoth Grey Stripe, remove spent blooms unless seed is being saved. Give the plant its listed spacing, cut flowers with clean tools, and leave selected heads to mature fully for seed. Expected emergence is 7-14 Days; the listed maturity or bloom timing is 80-89 Days.
Harvest, bloom, and uses
Mammoth Grey Stripe is suited to sunny borders, cut flowers, pollinator use, seed heads, and seed saving. Its yellow flowers and 97–120 in stature help determine whether it belongs in a border, cutting row, container, meadow edge, or restoration-style planting. Ornamental bloom and mature seed use depend on the named strain and harvest stage.
Saving seed
Save seed from several healthy, true-to-type Mammoth Grey Stripe plants identified before harvest. Confirm the pollination system of Helianthus annuus, separate compatible varieties that flower together, and remove clear off-types before they shed pollen or seed. Allow fruit, pods, ears, or seed heads to reach full biological maturity, then clean and dry the seed completely. Label the lot with variety, source, year, isolation method, number of seed plants, and any selection notes; store it cool, dark, and dry and test germination before an important planting.
Common problems
Common concerns: damping-off from saturated media; poor emergence from wrong temperature or depth; leggy seedlings from weak light; crowding and weak airflow; lodging in wind or rain; feeding damage from slugs, caterpillars, beetles, or mammals; foliar disease under prolonged leaf wetness; bird or squirrel feeding on maturing heads; stem lodging on giant plants. Management: use clean media, the sowing depth and temperature, strong light, appropriate thinning, and morning irrigation at soil level. Match support to plant height before wind becomes a problem. Inspect regularly and use the least disruptive control appropriate to the pest, plant, and pollinator setting. Remove diseased debris and rotate annual flower beds where recurring disease is severe.
Frequently asked questions
When is Mammoth Grey Stripe ready?
80-89 Days from sowing to the primary bloom or market stage used for the listed maturity range
How long does germination take?
Expect 7-14 Days near 65–80 °F; actual emergence changes with moisture, seed condition, and soil temperature.
How large does it grow?
About 97–120 in with an upright/erect habit. Support: Stake.
Can it grow in a container?
Best in the ground; a container would need to be exceptionally large, heavy, and stable
How is it used?
Primary role: Sunny borders, cut flowers, pollinator use, seed heads, and seed saving. Ornamental bloom and mature seed use depend on the named strain and harvest stage.
Can I save seed?
Yes where the crop biology allows, but keep compatible varieties isolated, use several healthy plants, wait for full seed maturity, dry thoroughly, and label the lot.
Minimum Seed Count:50 seeds
