William Robson Adams, 64, has been fined £370.
Police raided Adams' home at Great Orton, Cumbria, where they found around 5,000 wild snowdrop bulbs.
Locals noticed the flowers were missing and an investigation by the National Wildlife Crime Unit, working with local police officers found Adams had been digging up the bulbs at woodland in Dalston, Cumbria.
At Carlisle's magistrates' court, he admitted uprooting and trading in wild plant bulbs.
Police said he was a plant trader selling the bulbs online through Ebay and Amazon. The plants included bluebells, wild garlic and snowdrops, all of which are protected by the Wildlife and Countryside Act 1981.
Snowdrops are also protected under a section of the Control of Trade in Endangered Species (Enforcement) Regulations 1997, so they can only be sold if they have been legally acquired or lawfully imported. It is strictly against the law to take them from the wild and this means that their sale is a criminal offence.
Adams was charged with three offences of uprooting wild plants – snowdrops, bluebells, and wild garlic - and one of keeping unlawfully acquired snowdrops for sale.
He also faced a charge of fraud by misrepresentation, because he had advertised plants for sale as artificially propagated, when they had actually been unlawfully uprooted. Adams admitted all the offences.
The 5,000 bulbs which Adams took were all seized and then later replanted back into the wild by local volunteers.
Magistrates gave Adams maximum credit after hearing that he had fully cooperated with the police investigation. As well as the fines, he must pay a £20 victim surcharge and £85 costs.
Andy McWilliam, from the National Wildlife Crime Unit, said: "Basically, it’s an offence to uproot any wild plant.
"The law is there to protect species which would be at risk if the trade in them wasn’t controlled and people thought there was money to be made. We do occasionally get bits of intelligence that people are involved in this sort of illegal."