You say tomato, I say tomatillo
If there’s one vegetable that defines Mexican cooking, it has to be the tomatillo. Sometimes called ‘Mexican green tomatoes’, this warm season vegetable produces crisp, tart fruit that are surrounded by a distinctive papery husk similar to that of its close relative, the ornamental Chinese lantern. The fruit are deliciously versatile and can be chopped and used raw in salsas or cooked into a sauce for chicken or beef. Despite its exotic origins, tomatillos are an easy-to-grow crop that can yield abundant harvests even in the challenging British climate.
Tomatillos are handled in much the same way as tomatoes. Start them off as transplants by sowing seeds with artificial heat early in the year (see below). When the young plants are ready, transplant them into their permanent place where they will be cultivated and cropped. This could be inside an unheated greenhouse or tunnel, or in the warmer parts of the country, outdoors in a sheltered spot.
The plants grow perfectly well either in the ground, growbags, or large pots at least 7.5 liters in volume. If grown in the ground, pelleted chicken manure can be worked into the soil to provide enough nutrients for the entire season. For plants grown in growbags or containers, give a liquid feed once or twice a week to keep them going.
As they grow and develop, treat tomatillos like determinate bush tomatoes and do not remove the side shoots. Because they are large and sprawling, space the plants at least 60 to 90cm apart. The delicate branches are easily broken, and outside plants must be protected from strong winds. So far, tomatillos seem to be free from pests and diseases, making them an ideal vegetable for gardeners who want to avoid using sprays.
Tomatillos growing outdoors; tomatillo plants are large and sprawling
Tomatillos are afflicted by a condition called self-incompatibility, which means that a single plant cannot pollinate itself and produce fruit. To get around the problem, you need to grow at least two plants close together so that insects can move pollen from one plant to another and kick start fruit set.
Though tomatillos can be eaten when they are ripe, take a lesson from the Mexicans and use them when they are still green. The best time to harvest is when the fruit are plump and the husks have begun to split.
Tomatillos are harvested green when they have filled their outer husk
Using and Storing
To store tomatillos, refrigerate the fruit in a covered container, leaving the husks still attached – they should keep in good condition for about two or three weeks. Just before using, remove the husks and give the fruit a good wash – the outside is sticky, and dirt tends to collect there. The fruit can also be blanched and frozen in either plastic bags or boxes for off-season cooking.
Dehusked tomatillos ready for cooking.
Starting tomatillo transplants from seed
– Undercover crops: sow from the end of February to the middle of March.
– Outdoor crops: sow at the beginning of April.
Scatter seed into trays filled with a fine-textured compost and cover to a depth of 6mm. Maintain the compost at a temperature between 22 and 27ºC.
• When seedlings have three or four leaves, prick out into pots 8 to 9cm in diameter. Maintain an air temperature of 20 to 21ºC during the day, dropping it to 15 to 16ºC at night and during overcast days. After about a month, give the pots a feed of liquid fertiliser.
• Transplant the young plants when their roots fill the pots – this takes about 6 to 7 weeks after sowing:
– Undercover crops: transplant from the middle of April to the beginning of May.
– Outdoor crops: transplanted from end of May to the beginning of June.
The skeleton husk of a tomatillo
© Michael Michaud