Training melons and watermelons to grow vertically is referred to as trellising and is one of the advantages of growing melons in a high tunnel. Most melon cultivars and personal size (less than 7 pounds) watermelon cultivars are amenable to trellising.
A direct public offering (DPO), like the more traditional IPO, is a stock's introduction to the stock market. The stock is offered to the public for the first time. Unlike an IPO, which utilizes an underwriter to sell shares to the public, DPO shares are purchased directly from the issuing company.
If the existing shareholders approve the IPO, then the company can continue the process -- namely, securing investors. While it is filing its S-1 and getting shareholder approval, the company chooses the exchange it will electronically trade on.