How to Grow a Japanese Tomato

Plant Japanese Black Trifele seeds or seedlings in mid-spring, after the last frost, in sites with full sunshine, quick drainage and good air circulation. Grow this cultivar outdoors in areas with 3- to 4-month summers.

Set out a 10-square-foot site for growing Japanese Black Trifele tomatos. Dig into the top 10 inches of soil throughout the site to loosen the foundation, and add 4 to 5 inches of organic compost for moisture and nutrition. Add 6-24-24 or 8-32-16 starter fertilizer, per the manufacturer's directions, to give tomato seeds or seedlings a quick start.

Plant Japanese Black Trifele tomato seeds 1/2 inch deep, and plant seedlings in holes wide and deep enough for their root balls. Plant the tomatoes at 30 to 36 inches in the row and with 4 feet between rows. Japanese Black Trifele tomato plants are indeterminate and require more generous spacing than smaller determinate tomato plants.

Water each tomato plant with 2 inches of water every week to keep the soil moist, and use 2 to 3 inches of organic mulch in the plot to maintain moisture and warmth. Use a trellis system or stakes for each plant to support the indeterminate vines during growth.

Feed Japanese Black Trifele tomatoes with 10-10-10 fertilizer at the first fruiting. Follow the manufacturer's directions in regards to fertilizer application and safety. Fertilize the plants again 2 weeks after the first harvest and then again 1 month later.

Harvest Japanese Black Trifele tomatoes at 80 to 85 days, when the fruit begins to ripen. Allow fruit to ripen on the vine for the sweetest, juiciest harvest.