Merbein Seedless: Sunraysia’s home-grown sultana alternative (and a quiet CSIRO success story)

If you’ve spent any time around vineyards in Sunraysia, you’ll know this region doesn’t just grow fruit — we’ve helped shape what Australia grows.

One of the best examples is Merbein Seedless, a dried-grape variety bred right here at the CSIRO Merbein site as an alternative to the traditional sultana (Thompson Seedless).

It’s the kind of local innovation that doesn’t always get the spotlight… but it’s been quietly backing our dried-fruit industry for decades.

So what is Merbein Seedless?

In simple terms: Merbein Seedless is a white, seedless grape bred primarily for drying, developed by CSIRO at Merbein and released to industry in 1981.

While “sultana” often gets used as a catch-all term for dried grapes, Merbein Seedless was specifically bred as a sultana alternative — aiming for traits that help growers in real-world Sunraysia conditions. 

Why CSIRO bred it in the first place.

Back in the 1970s and 80s, CSIRO’s dried-grape breeding program was focused on building varieties that could outperform the mainstays of the time (like Thompson Seedless), with improvements across the board. Things like reliable fruitfulness, rain tolerance, and suitability for modern production methods. 

That focus makes perfect sense for our patch of the world. We’re productive, we’re export-minded and we’re also at the mercy of whatever the season throws at us.

What makes Merbein Seedless different?

According to industry variety notes, Merbein Seedless comes with a handful of practical advantages that would’ve been very attractive to growers:

• Earlier maturity — it can mature in early February, ahead of traditional sultana. 

• Fast drying — reported to dry in around 7–10 days when summer pruned.

• Late budburst — meaning it can be useful in frost-prone areas. 

• Rain resilience — it’s been reported to survive pre-harvest rain events without splitting. 

Those are the kind of traits that matter when you’re making decisions measured in seasons, not weekends.

Not perfect — but that’s farming

Like most varieties, Merbein Seedless also has its quirks. The same variety notes flag some management challenges, including that it can be hard to maintain a healthy cordon, and that replacement fruiting canes can be tricky to manage and space.

That’s the reality of viticulture, every variety is a trade-off, and the “best” one often depends on your block, your trellis, your soil, and your risk profile.

A bigger Merbein story than just one variety

Merbein Seedless sits in a broader CSIRO legacy of dried-grape development that has delivered multiple releases over the years (with Merbein Seedless listed among those outcomes). 

And that’s worth remembering whenever we talk about Sunraysia’s role in Australian horticulture: we’re not only producing fruit — we’ve helped develop the genetics and know-how that keep entire industries moving.

The local pride 

There’s something pretty special about the name “Merbein Seedless” being attached to an agricultural variety that’s been grown and evaluated beyond our region. It’s a small stamp of Sunraysia on the wider dried-fruit world, the sort of thing locals should be quietly proud of.

Because while cities might build their reputations on coffee lanes and stadiums, we build ours on innovation you can eat.