Shellfish and Crustaceans: A Seasonal Guide to Freshness

Shellfish can be incredible… or seriously disappointing. We’ve all had that plate of prawns that tasted like nothing, or mussels that smelled a bit too “harbour-y” to be reassuring. And nine times out of ten, the problem isn’t the recipe. It’s the season. Eating shellfish at the right time of year changes everything. Texture, flavour, even how safe and fresh it feels on the plate. So yeah, seasons matter. A lot.

In fact, once you start paying attention to seasonality, you notice it everywhere. Fishmongers’ stalls look different. Menus change. Even places obsessed with seafood, like https://restaurant-coque.fr, build their dishes around what’s actually good right now, not what looks nice on a supplier’s list. And honestly, that’s usually where the best meals come from.

Why seasonality makes such a big difference

Here’s the thing people don’t always realise : shellfish are living creatures, deeply affected by water temperature, reproduction cycles, and food availability. When they’re in season, they’re plump, firm, full of flavour. Out of season ? They’re often watery, bland, or worse, stressed and fragile.

There’s also the safety side. Warmer months increase the risk of bacteria in certain shellfish, especially bivalves like oysters. That old rule about only eating oysters in months with an “R”? It’s not folklore pulled out of thin air. It came from real-world experience, long before fridges and refrigerated transport.

So if you’re asking yourself, “Why didn’t this lobster taste amazing ? It cost a fortune.” Well… maybe it just wasn’t the right month.

Oysters : winter is their moment

I’ll say it straight : oysters in summer are rarely worth it. From September to April, though ? Totally different story.

In colder months, oysters aren’t spawning. Their flesh is dense, creamy, almost buttery. You open one and it smells clean, like cold seawater and rocks. No weird sweetness, no milkiness. Personally, January oysters are my weakness. After the holidays, grey skies, cold hands… and then that briny hit. Magic.

Summer oysters can be eaten, sure, especially farmed ones. But flavour-wise ? I find them thinner, sometimes a bit dull. If you want the wow factor, stick to autumn and winter.

Mussels : best when the water is cold

Mussels are forgiving, but they still have a sweet spot. In the UK and much of Europe, that’s roughly October to March.

Cold water means slow growth, which equals better texture. The flesh is firm, slightly sweet, not watery. When you steam them, the broth turns cloudy and rich. That’s a good sign.

In late spring and summer, mussels often spawn. You’ll see it immediately : pale, mushy flesh that falls apart. Are they dangerous ? Not necessarily. Are they enjoyable ? Honestly… not really. I usually skip them once the weather warms up.

Crabs : timing is everything

Crab is tricky. Blue crab, brown crab, spider crab… each has its rhythm. But one rule stands out : avoid soft-shell periods unless you know exactly what you’re doing.

In the UK, brown crab is best from late summer through winter. That’s when the meat is fullest, especially in the claws. You crack them open and there’s resistance, weight. That’s what you want.

Early spring crabs can look decent but feel hollow. You pay for shell, not meat. It’s frustrating. Been there, regretted it.

Lobster : not just a luxury, a seasonal product

Lobster has this image of being great all the time. In reality ? Not quite.

Late spring to early autumn is generally best, depending on local waters. That’s when lobsters have hardened shells and packed tails. The meat is sweet, dense, almost crunchy when cooked properly.

In winter, many lobsters are soft-shelled. They’re alive, yes, but the yield is disappointing. If you’ve ever pulled a lobster tail apart and thought, “Wait… that’s it ?” – yeah, wrong season.

Prawns and shrimp : farmed vs wild matters

This one surprised me when I first learned it. Wild shrimp are highly seasonal. North Sea brown shrimp, for example, peak in autumn. They’re tiny but insanely flavourful. Sweet, iodine-rich, perfect just boiled with a bit of salt.

Farmed prawns, on the other hand, are available year-round. But availability doesn’t mean quality. Texture varies wildly. Some months they’re snappy and juicy, other times a bit rubbery. If your prawns smell overly sweet or chemical, trust your nose and walk away.

So… how do you actually choose well ?

A few simple habits make a huge difference :

Ask questions. Seriously. A good fishmonger loves talking about seasons. Trust your senses. Fresh shellfish smell clean, never “fishy”. Don’t chase everything at once. If oysters are perfect right now, enjoy them. Lobster can wait. Accept limits. Just because you want crab in March doesn’t mean it’ll be good.

And ask yourself this : would you rather eat something because it’s available, or because it’s at its absolute best ?

Because when shellfish are in season, you don’t need fancy sauces or complicated techniques. A bit of heat, some salt, maybe lemon. That’s it. The rest ? The season does the work for you.