Updated 11 September 2026
Slippery Jack in Uppsala, Sweden: live forecast and 14-day outlook
The best time for slippery jack in Sweden is August to November, with the peak normally in the middle of that range. Today they’re at 65% and looking good in Uppsala
It fruits after warm late-summer and autumn rain, typically when day temperatures sit around 10 to 20C and the ground stays damp. A good soaking followed by mild nights usually brings flushes within a week or two.
In the same pine woods and season look for other Suillus such as larch bolete and weeping bolete, plus saffron milkcaps and the occasional bay bolete or porcini on richer patches. False chanterelles and various brittlegills often share the same acidic ground.
Use fresh within a day or two as the slime makes it perish quickly; peel and clean before chilling. It dries well once peeled and de-pored, and the dried slices or powder keep for months in an airtight jar; it can also be cooked and then frozen.
Other Suillus boletes such as the larch bolete (Suillus grevillei) and weeping bolete, all of which are also edible, so there are no dangerous poisonous lookalikes. The slimy brown cap, yellow pores and ringed stem set it apart from any toxic gilled mushroom.
Uppsala sits on the flat, fertile Uppland plain, low-lying farmland threaded by the Fyrisån river and the long gravel eskers left by the ice age. South and east the land gives way to the bays of Lake Mälaren and the Baltic coast, while gentle forested rises take over to the north. Boreal conifer forest dominates, mostly Norway spruce and Scots pine mixed with birch, aspen and alder. Mushrooms favour the mossy spruce stands, the damp birch edges and the bogs and pine heaths common across reserves like Hågadalen-Nåsten and Norra Lunsen.
The climate is humid continental, with cold, snowy winters and mild summers. The decisive rains come in late summer and early autumn, and it is this damp warmth that triggers the main fungal flush. Foraging here is easy and rewarding thanks to the right to roam, with chanterelles arriving around midsummer and porcini, funnel chanterelles and other autumn species following into October. Spruce and birch woods within easy reach of the city make Uppsala a generous region for beginners and seasoned pickers alike.
FAQ
Where do slippery jack grow in Uppsala, Sweden?
Grows in conifer woods, almost always with pine, on sandy or poor soil and often along forest tracks and clearings. Common in young plantations and appears in groups. They tend to come back to the same kinds of ground year after year, so once you find good cover it is worth checking again. ShroomCast does not share exact spots; it tells you the timing for Uppsala, Sweden so you know when it is worth heading out.
How do I know slippery jack season has started in Uppsala, Sweden?
Season usually kicks off after a warm spell followed by steady rain, with the first flushes appearing somewhere in the August to November window. The clearest sign is the live forecast lifting off zero into ‘just starting’ or ‘building’. For Uppsala, Sweden it currently sits at 65% and is looking good.
Are slippery jack out near me right now in Uppsala, Sweden?
Today the slippery jack forecast for Uppsala, Sweden is 65% and conditions are looking good. That is a live read for the region this September, and it shifts with the weather rather than following a fixed calendar. It tells you if it is worth heading out in Uppsala, Sweden right now.
What should I look for this week for slippery jack in Uppsala, Sweden?
This week in Uppsala, Sweden the forecast is 65% and looking good. Grows in conifer woods, almost always with pine, on sandy or poor soil and often along forest tracks and clearings. Common in young plantations and appears in groups. The 14-day outlook on the page shows whether conditions are climbing toward a flush or easing off, so you can pick your day.
Is it mushroom season in Uppsala, Sweden right now?
For slippery jack in Uppsala, Sweden, the typical season is August to November, and today the live forecast reads 65% with conditions looking good this September. So yes or no depends on the day and the weather, which is exactly what the forecast tracks.
See the live regional forecast in the ShroomCast app.
This page shows today. The app gives you the full 14-day outlook for your area and all 14 species, so you can pick the right day before you drive out.
Scale: 0-20% very low · 20-40% low · 40-60% moderate · 60-80% high · 80-100% excellent. ShroomCast forecasts fruiting probability from weather, soil, forests and years of observations – a guide, not a guarantee of finds.
ShroomCast forecasts the region and the time of year. It cannot identify mushrooms for you, so confirm any species with a reliable source before eating it.