A sign staked in the median of North Arthur Ashe Boulevard in Richmond reads “Grow your four.” Just up the street, Happy Trees Agricultural Supply is helping people get ready to do just that. With rows of fertilizer, lights and other hydroponics supplies, Happy Trees co-founders Josiah Ickes and Christopher Haynie are preparing people to grow their own marijuana plants in their homes.

That’s because on Thursday, Virginia becomes the first state in the South where it’s legal for people 21 and older to possess and grow small amounts of pot.

Over the past few weeks, the five phone lines at Happy Trees have been flooded with calls from eager customers inquiring about growing supplies, how to get started and what exactly will become legal once the law is enacted on Thursday.

“They’re asking us grow questions and things about that as we prepare for July 1,” Ickes said. “But they’re also trying to understand the law. They’re trying to understand what does this all mean?”

Virginia is one of 18 states, plus the District of Columbia, to legalize the recreational use of marijuana in the United States, an effort that reflects growing cultural acceptance of the plant and a desire to minimize disparate enforcement against people of color. Marijuana remains illegal under federal law.

Virginia legislators originally voted to legalize adult recreational use with plans for the law to come into effect in 2024, when retail sales are scheduled to begin. But, after a push from activists and concerns over three more years of enforcement, lawmakers voted in April to move up legalization to July 1 of this year. Retail sales are still not slated to begin until 2024.

The sudden shift and differing timelines left Virginians excited to participate, but stuck with questions regarding what exactly will be legal come Thursday.

Some answers:

●Adults 21 or older may possess up to an ounce of marijuana and cultivate up to four marijuana plants per household.

●Selling or buying marijuana will still be illegal (selling is also illegal in D.C.). But it will be legal to gift up to an ounce of marijuana to another adult.

●Smoking or consuming marijuana is also only legal in private. Smoking it in public is not legal, nor is an “open container” of it in a vehicle.

●Possessing more than an ounce but less than a pound of marijuana would result in a civil penalty of up to $25; more than a pound is considered a felony punishable by up to 10 years in jail and a fine of up to $250,000.

Businesses like Happy Trees, and advocacy groups across the state, have been working to educate the public, especially about some of the smaller provisions, so Virginians can safely participate within the confines of the law.

Ashna Khanna, ACLU of Virginia legislative director, emphasized the importance of being cautious and informed about what is legal while police and communities adjust to the new laws.

“It is really imperative, during this time, that folks are really careful about how they go about the marijuana laws,” Khanna said. “It’s going to be a process, both for Virginia and the police and the communities, to all get aligned on how these laws are going to be implemented and play out.”

Khanna discussed the almost 300-page legislation, its complexity and some of the unanswered questions and uncertainty about how this is going to play out, like what exactly constitutes as an “open container” in a vehicle. People should try to keep marijuana out of their cars, or put it in the trunk if necessary, Khanna said, until there’s a better idea of what open-container enforcement looks like.

“I think there’s this level of excitement,” Khanna said. “But also a lot of nervousness and a lot of questions that are coming up.”

In Tysons, in Northern Virginia, Ben Dyer and his business partner, Rudy Lovato, started DMV Grow House in April, a hydroponics shop that offers in-house assistance to people trying to cultivate and maintain plants.

“We’re not just setting up grows and maintaining them, but educating them on what they can and can’t do,” Lovato said. “We need to educate people that this is okay to do.”

DMV Grow House has been operating in what Lovato called the “gray area” of the law, waiting for it to “turn green.” In the past couple of weeks, DMV Grow House has increased its online and advertising presence to get ready for new customers who are interested in cultivating their four legal plants.

Dyer and Lovato said they’ve watched other states around the country go through the legalization process, and feel confident about the industry and Virginia’s new law since it has other models to follow.

“We got to watch what they did for all the ones that came before us,” Lovato said. “That’s why Virginia is the best one out of all of them.”

Others aren’t convinced about the efficiency of Virginia’s law, especially with the sped-up timeline.

State Sen. Bill DeSteph Jr. (R-Virginia Beach) voted against the legislation in February and April — citing issues with what he considered to be contradictory language and confusing provisions in the law.

“To me, this is just conflicting and doesn’t make sense,” DeSteph said about it being legal to possess but illegal to purchase recreational marijuana.

DeSteph especially took issue with a provision in the legislation instructing the state to give preference when awarding marijuana-related business licenses to groups that have suffered the most from the criminalization of the drug. He said he wished legalization would have been delayed until 2024, like originally planned, to give the state more time to work out the kinks of the bill.

“If it would have been done right, I would have supported it all day long,” DeSteph said.

Advocacy groups are hailing Thursday as victory, but similarly note there’s still work to do on the legislation. A lot of measures and framework for the retail sector will be subject to change before sales begin in 2024, and Virginia lawmakers will have to approve legislation relating to marijuana legalization again next year during the general session.

Until then, people are preparing to take advantage of the new law and get smoking. To celebrate legalization, a group called Virginia Marijuana Justice organized “The Great Commonwealth Cannabis Seed Share” on Thursday. In locations around the state, the organization will give away seeds that were donated by growers.

At Happy Trees in Richmond, Ickes said about 90 percent of their customers are newcomers who aren’t familiar with the growing process. Their business has doubled month after month since legalization was announced, he said, attracting all types of purchasers.

“We have people who’ve never grown a house plant coming in to get ready to go for July 1,” Haynie said.

Their first customer in the shop on Friday morning was a man purchasing fertilizer and lights to grow his own cannabis — something he had never done before, Haynie said.

He was buying it as a gift to himself for his 72nd birthday.