Caren White is a Master Gardener and instructor at Home Gardeners School. She has been associated with Rutgers Gardens for over a decade.
What are Tomatillos?
Tomatillos (Physalis ixocarpa) are members of the nightshade family which includes tomatoes, eggplants and peppers. Also known as husk tomatoes because the fruit is surrounded by a husk, they are native to Central America. They are the base for Mexican salsa verde or green sauce.
Tomatillos are only perennial in zones 10 – 11, so they are usually grown as annuals. In one season, they will grow to 1 ½ - 3 feet tall and 18 – 24 inches wide. They require support like tomatoes. You can either stake them or use tomato cages to keep them from falling over. If the stems are allowed to touch the ground, they will develop roots and your plant will sprawl rather than grow upright.
Tomatillo leaves look like eggplant leaves. The flowers can be purple, yellow or light green.
The fruit develops in a paper-like husk. When the fruit is ripe, it will fill the husk completely.
If you don’t harvest the fruit, it will outgrow the husk then drop seed in your garden, and reseed the following year.
How to Grow Tomatillos
Tomatillos like full sun and rich, well-drained soil with a neutral pH. They do not grow in cool soil, so wait until after your last frost when both the air and the soil have warmed enough to plant. In my NJ zone 6 garden, I plant my warm weather vegetables at the end of May. It’s a good idea to enrich your soil by mixing in some compost before planting.
You will need to plant 2 or more plants to ensure pollination. If you only grow one plant, you won’t have any fruit. You need at least one additional plant to pollinate the flowers. Plant them deep enough so that you can bury 2/3 of the stem of each plant. The stems will develop roots just like tomato plants do. Because the plants grow so large, you want a large root mass to support them. Space your plants 3 feet apart.
When you are planting your tomatillos is also a good time to insert stakes or tomato cages to support the plants as they grow. If you wait until the plants are larger, you risk injuring or killing the roots as you push the stake or tomato cage into the soil. Do it during planting so that the roots can grow uninjured around the stake or cage.
Tomatillos need 1 – 1 ½ inches of water per week. Don’t let your plants dry out. A good way to keep the soil moist is to put down a thick, 2 – 3 inch layer of mulch. This will not only help the soil to retain water but it will also prevent weed seeds from germinating and then competing with your plants for sunlight, water and nutrients.
How to Grow Tomatillos From Seed
Tomatillos can be grown from seed. You will want to start them indoors 6 – 8 weeks before your last frost. Plant the seeds ¼ inches deep in containers filled with pre-moistened soil. I like to moisten my soil before I plant seeds because I have found if I use dry soil and then try to water the containers after planting the seeds, the soil and seeds will just wash away. So I plant my seeds in pre-moistened soil and then give them a good watering afterwards. Germination should occur in 1 -2 weeks.
You can transplant your seedlings outdoors after your last frost when the soil has warmed. The plants will not grow in cold soil. In my NJ zone 6 garden, I plant my warm weather veggies like tomatillos at the end of May. Be sure to space your plants 3 feet apart.
How to Harvest Tomatillos
Tomatillos are ready to harvest when they have completely filled the husk. They should be firm to the touch and pull easily away from the plant. You can either harvest them when the fruit is green (good for salsa verde) or wait a little longer until the fruit has split the husk and turned purple or yellow depending on the cultivar. At this stage they are sweeter than green fruit and often used in jams or preserves rather than fresh.
How to Store Tomatillos
You can store your freshly harvested tomatillos, still in their husks, in a paper bag in your refrigerator for 2 – 3 weeks. You can also freeze the fruit. Remove the husk and wash the fruit. Dry them thoroughly and place them in freezer bags. Double bag them to make sure that they don’t develop freezer burn. Frozen, they will keep 2 – 3 months.
© 2020 Caren White