Grapefruit Superstar

Grapefruit Superstar Cannabis Seeds by Amsterdam Genetics

Grapefruit Superstar is a sativa-dominant feminized cannabis seed strain (90% sativa, 10% indica) that delivers sweet citrus flavours and a fast flowering time of just 8 weeks. Bred by Amsterdam Genetics from a cross of Cinderella 99 and Superfast Growing Sativa, she's built for growers who want speed and flavour without babysitting their plants. With indoor yields averaging 500g/m² and a THC content around 20%, this one punches well above her weight class.

Why Grapefruit Superstar Cannabis Seeds Deserve Your Grow Space

We've seen a lot of sativa-dominant strains come through the shop over the years, and the ones that stick around tend to share two traits: they don't take forever to flower, and they actually taste as good as the breeder claims. Grapefruit Superstar ticks both boxes. An 8-week flowering period is unusually fast for a 90% sativa — most sativa-heavy genetics push you past 10 or even 12 weeks, which tests your patience and your electricity bill. Amsterdam Genetics achieved this by crossing Cinderella 99 (already famous for her speed and citrus profile) with their proprietary Superfast Growing Sativa. The result is a plant that grows with sativa vigour but finishes on an almost indica-like schedule.

The flavour is the real selling point, though. Crack open a cured bud and the room fills with pungent grapefruit — tangy, sweet, unmistakably citrus. It's not a subtle background note; it's front and centre, in the jar, in the grinder, and especially through a vaporiser where the terpene profile really opens up. If you've grown Cinderella 99 before, you'll recognise the family resemblance, but Grapefruit Superstar pushes the citrus further and adds a richer sweetness underneath.

One honest heads-up: she grows tall. Properly tall. Outdoors, she can hit 3 metres, and even indoors she'll stretch aggressively during the first weeks of flower. If you're working with a 120cm tent, you'll need to top her early and possibly run a SCROG net to keep the canopy manageable. In a taller space or outdoors, just let her rip — that vertical growth translates directly into more bud sites and bigger harvests.

Grapefruit Superstar Growing Specifications

Flavour and Aroma Profile of Grapefruit Superstar

If you've ever peeled a fresh pink grapefruit and that sharp, sweet spray hit your nose — that's what opening a jar of Grapefruit Superstar smells like. The aroma is immediate and pungent: citrus-forward with a sugary undertone that rounds off the tartness. It's not a one-note citrus either. There's depth to it — a tangy sharpness on the inhale that mellows into something richer and sweeter on the exhale.

Through a dry herb vaporiser set around 185-195°C, the terpene expression is at its best. You get the full citrus spectrum without combustion muddying the flavour. Smoked in a joint, the sweetness comes through more prominently, with the grapefruit tang sitting underneath. Either way, this is one of the more flavourful sativa strains we've come across — the Cinderella 99 parentage really shines through in the taste department.

For comparison: if you've grown or smoked Lemon Haze and enjoyed the citrus angle but wanted something less sharp and more sweet, Grapefruit Superstar sits in that sweet spot. Less acidic, more tropical, with that distinctive grapefruit bitterness that keeps it interesting.

How to Grow Grapefruit Superstar Cannabis Seeds

1. Germination: Use the paper towel method or soak seeds in water for 12-24 hours until taproots appear. Transfer to small pots with light, airy soil or a coco/perlite mix. Keep the environment warm (22-25°C) and moist but not waterlogged.
2. Vegetative stage: Grapefruit Superstar grows fast and tall during veg. Indoor growers should top the plant once she has 4-5 nodes to encourage lateral branching and control height. A SCROG net is your best friend here — spread those branches out to maximise light exposure across the canopy.
3. Light management: She adapts well to various light conditions and can handle lower-light environments, though you'll get the best yields under strong lighting. A 600W HPS or equivalent LED over a 1m² canopy is a solid starting point. She's not fussy, but she rewards good light with denser buds.
4. Flip to flower: Switch to a 12/12 light cycle when the plant has filled roughly 60-70% of your canopy space. Expect significant stretch in the first 2-3 weeks of flower — sometimes doubling in height. Plan your flip accordingly. Flowering completes in approximately 8 weeks.
5. Feeding: Standard sativa feeding schedule works well. She's not a heavy feeder in veg but appreciates a boost of phosphorus and potassium during mid-to-late flower to support bud development. Watch for nitrogen toxicity — sativas tend to show it faster than indicas.
6. Harvest: Check trichomes with a jeweller's loupe. For the full cerebral, energising effect, harvest when trichomes are mostly cloudy with minimal amber. You can expect around 500g/m² indoors with proper technique. Outdoor plants in warm climates can yield even more given the space to reach full size.
7. Drying and curing: Hang branches in a dark room at 18-20°C with 55-60% humidity for 7-10 days. Once stems snap rather than bend, trim and transfer to glass jars. Burp daily for the first two weeks. The citrus terpenes really develop during a proper cure — give her at least 3-4 weeks in the jar for the best flavour.

Grapefruit Superstar vs Other Sativa Seeds

Compared to a classic like Amnesia Haze, Grapefruit Superstar finishes 3-4 weeks faster while delivering a comparable cerebral effect. The trade-off is that Amnesia Haze tends to produce slightly higher THC levels (up to 22-24%), but the difference in flowering time makes Grapefruit Superstar a more practical choice for indoor growers running multiple cycles per year.

If speed and ease of growing are your priorities, Grapefruit Superstar is the clear pick. If you want maximum THC and don't mind waiting, Amnesia Haze is worth the extra weeks. Super Silver Haze sits somewhere in between but lacks the distinctive sweet citrus flavour that makes Grapefruit Superstar stand out.