Description

Indica-dominant FAST version with very good yields and THC production.

This is an ultra-fast flowering, photoperiod-dependent, feminized strain that develops red flowers. Black Muffin F1 Fast Version® is a first filial generation (F1) cross between a photoperiod-dependent elite clone from our Red Hot Cookies® and the select autoflowering strain Black Lemon Auto.

The strain has a vigorous hybrid character and grows long side branches with thick, compact buds that are soaked with aromatic resin. The buds turn a dark purple color in the flowering stage, emitting a thick, potent, sweet-and-sour aroma with fresh citrus tones of lemons and mandarins, plus a tart undertone of red berries.

Black Muffin F1 Fast Version® has an intense yet balanced, relaxing, and happy effect that stimulates conversation and the imagination.

Characteristics

Brand/breeder

Sweet Seeds

Parental lines

Red Hot Cookies x Black Lemon Auto

Type

Indica dominant

Color

Purple

Flowering type

Early/fast

Sex

Feminised

THC potential

Very High THC (25%+)

CBD potential

Low CBD (0-1%)

Yield potential outdoor

High Yield (450-750gr/plant)

Yield potential indoor

High Yield (450-600gr/m2)

Flowering time (photoperiod)

6 to 8 weeks

Suitable climate

Dry, Hot, Temperate, Warm

Aroma

Fruity

SKU

SS-BLMF1-FAST-FEM

Grow guide

Early/Fast outdoor timeline

Fast / Early strains keep the photoperiod growth pattern, but they begin flowering earlier and usually finish sooner — helping outdoor growers harvest before late-season weather becomes a problem.

Stage 1

Germination / Early Start

March – April

Wait for: warmer days, lower frost risk, stable spring weather

Watch for: cold snaps, excess moisture, slow early growth

Stage 2

Seedling / Transplant

May

Wait for: steady light, mild conditions, protected early growth

Watch for: transplant stress, pests, wind exposure

Stage 3

Vegetative Growth

June – July

Wait for: long bright days, healthy expansion, strong structure

Watch for: overcrowding, nutrient issues, insect pressure

Stage 4

Flowering

From late July

Wait for: first signs of bloom, good airflow, settled conditions

Watch for: humidity, mould pressure, poor weather

Stage 5

Harvest

From early September

Wait for: ripe trichomes, dense finished flowers, harvest readiness

Watch for: cutting too early, rain, bud rot

Indoor Early/Fast timeline

Fast / Early strains are most valuable outdoors, where earlier flowering and shorter bloom times help growers harvest before poor autumn weather. Indoors, their main benefit is a faster flowering phase than photoperiod versions.

Week 0

Germination

Healthy seedling emergence

Wait for: healthy seedling emergence

Watch for: overwatering, weak starts

Week 1–2

Seedling

Steady early growth

Wait for: steady early growth

Watch for: stretching, stress, excess moisture

Week 3–6+

Vegetative Growth

Desired plant size and strong structure

Wait for: desired plant size and strong structure

Watch for: overcrowding, uneven growth, training stress

6–10 weeks

Flowering Phase

Strong bud formation and steady flower development

Wait for: strong bud formation and steady flower development

Watch for: humidity issues, poor airflow, plant stress

Harvest

Harvest Window

Finished flowers and mature trichomes

Wait for: finished flowers and mature trichomes

Watch for: harvesting too early or pushing plants too long

Reviews

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We found matching review(s) Clear filters

Marino Proscia 12.06.2026

buyer

Still in dryer One bean was male.

Marino Proscia 12.06.2026

buyer

Still in dryer

As described: YesExpected Yield: AboveRecommend to others: Yes

Jim Gregory 29.06.2024

Found Strain: Seedsman Website

buyer

Really nice seed to begin with. Big beautiful leaves, nice branching. Big plants. Still vegging.

As described: YesRecommend to others: Yes

Seedsman (30.10.2026): Thank you for your review! We really appreciate all those who take time to leave us feedback. We have done a lot of improvements to our website and the way we work. We now have a quicker, better website with products that are easy to find. An excellent, diverse range of the most exciting seeds, combined with what we aim to be, the best service. Our new customer service bot Barbara has just been released and can help all our customers on our website or social media answer any important questions on their order, the ordering process, or any grow questions. Our mission is to ensure our customers have no reason to shop elsewhere. We hope you like the direction we are heading in. Please come back and shop again soon and recommend us far and wide. Thank YOU! Best Seedsman P.S. in the USA we also now have clones available.

Anonymous 25.06.2024

buyer

Wow Sweet Seeds Fast strains are fantastic. Healthy robust genetics and crazy stretching in flower. Nice

As described: YesExpected Yield: Expected

Seedsman (30.10.2026): Thank you for your review! We really appreciate all those who take time to leave us feedback. We have done a lot of improvements to our website and the way we work. We now have a quicker, better website with products that are easy to find. An excellent, diverse range of the most exciting seeds, combined with what we aim to be, the best service. Our new customer service bot Barbara has just been released and can help all our customers on our website or social media answer any important questions on their order, the ordering process, or any grow questions. Our mission is to ensure our customers have no reason to shop elsewhere. We hope you like the direction we are heading in. Please come back and shop again soon and recommend us far and wide. Thank YOU! Best Seedsman P.S. in the USA we also now have clones available.

Please note that some customers choose to leave a rating without writing a review, and because of this the number of ratings will differ from the number of reviews.

Black Muffin F1 Fast Feminized Seeds

Flowering Type

Early/fast

Parental lines

Red Hot Cookies x Black Lemon Auto

THC content

Very High THC (25%+)

CBD content

Low CBD (0-1%)

Photoperiod flowering time

6 to 8 weeks

Yield indoor

High Yield (450-600gr/m2)

Suitable climates

Dry, Hot, Temperate, Warm

Early/Fast outdoor timeline

Indoor Early/Fast timeline

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