It may take a bit of your time, but you could plant a couple birds of paradise and fertilize them with the fertilizer from Ivor, fertilize them four times each and tap it four times when it is finished growing. Make sure you sell the stem before it disappears. Repeat until you get your desired amount of coins. You could use a cocoadile to fertilize the plant, too. This should take about 5-10 minutes to get 25,000 coins