Although he had almost no experience in that field, the topic interested him. So in 2010 he decided to take part in Estonia's biggest business innovation competition, Ajujaht, or Brainhunt in English, to develop a simple system for growing edible plants at home.
The idea won the competition, and the resulting startup, Click & Grow, was already beginning to sell its first products a year later.
Fast-forward to 2018 and the company is already producing its third generation of Smart Indoor Gardens, which allow 27 plants to be grown simultaneously.
The company's technology involves a simple automated system, consisting of special Smart Soil and adjustable LED grow lights.
"We have around 450,000 customers, most of whom are home users. They're men and women aged between 20 and 40 years, who live in bigger cities but still want to experience the closeness to nature that a garden like this provides them with," Lepp tells ZDNet.
In addition to foodies who want to grow their own vegetables, there are also botanists who are interested in growing sometimes quite unusual plants with the product.
"The most memorable was a customer who grew sequoia trees with their garden," Lepp says.
Recently, Click & Grow added bigger Wall Farms to the selection, enabling customers to grow up to 51 plants simultaneously. Lepp says the Wall Farms have proven successful among corporate buyers, because they add "great vibes" to the office environment. The product is also raising interest in the hospitality industry.
"We're also seeing a growing number of restaurants buying our Wall Farms to grow their essential herbs and greens with us," he said.
Click & Grow views Aerogarden, Plantui, and Sprouts.io as its main rivals in the market. Lepp says his company's growing technologies are what make it different.
"Our competitors are using hydroponics where the user needs to continuously add nutrients, whereas we use soil-based technology that has just the perfect amount of nutrients already inside," he says.
According to Lepp, the Smart Soil makes sure plants have just the right amount of oxygen, nutrients and root space to produce maximum results. Each soil pod is fine-tuned for the need of the plant seed that it contains.
He believes that the indoor gardening sector has the potential to grow at least five times bigger than its current size.
"One of the most significant challenges and growth barriers for the industry is the price. The challenge is how to get the price level for hyperlocal farming to match that of the plants we buy in supermarkets today."
Click & Grow employs 42 people in Estonia but it also has an official representation and office in the US.
The production takes mainly place in Estonia, only plastic parts are manufactured in China.
In late October this year, the company closed its latest financing round led by Estonian-based United Angels VC alongside two strategic investors: INGKA Group, the world's largest home-furnishing retailer operating 367 IKEA stores, and SEB Alliance, the corporate venture arm of French Groupe SEB.
So does the INGKA strategic investment mean Click & Grow products will at some point be sold in IKEA's stores?
"INGKA has been testing our products for a year. They are our strategic investor, and we're working towards extending our co-operation in many ways. Today it's too early to add further details," he says.
But he adds that with the investment Click & Grow's primary goal is to strengthen its foothold in the US where a big chunk of the company's sales are already generated.
"Our product is ideal for customers living in urban areas. Therefore, our main markets correlate well with areas where the percentage of people living in cities is high, such as Northern America, with 82 percent of the total population. In Europe, the UN suggests that 74 percent of people live in towns," he says.
Another goal is to enter the Chinese market.
"We're witnessing a growth in the number of wealthy, middle-class residents in the world's largest cities and an increasing trend towards urbanization," he says.
"With this in mind, China is a country where we see very high potential for indoor gardening products," Lepp says, adding that in five years he hopes to add North Africa to the markets where the company is present.
In the near future, Click & Grow will continue to focus on the home and office segment.
"We're also continuously developing our larger products to ensure the product market fit is at the required level for fast scaling," explained Lepp.
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