How to Grow Tomatillos
Plant two, or you will get flowers and no fruit.
Tomatillos look like green tomatoes in paper lanterns and behave nothing like them. They are the sour, citrussy base of a salsa verde, they crop enormously, and they have one requirement people miss until it is too late.
You need two plants
Tomatillos are almost entirely self-incompatible. A single plant will flower for weeks and set almost nothing, and it looks exactly like a pollination failure because it is one. Plant at least two, and preferably three, for a proper crop.
This is the single most common reason a first tomatillo crop disappoints.
Sowing and planting
Sow in September, October, November, December. Treat them like tomatoes: start under cover if your spring is cold, plant out after the last frost once the soil has warmed, and bury the stem deep because they root along it.
Space them a metre apart. They sprawl far wider than a tomato and a crowded row becomes an impenetrable thicket.
Growing them
- Stake or cage them. The plants get heavy and sprawl, and fruit on the ground rots.
- Do not overfeed. Rich nitrogen gives a huge bush and little fruit, exactly as with tomatoes.
- They are tougher than tomatoes about heat, drought and disease, and they are rarely troubled by blight.
- Expect volunteers. Dropped fruit seeds itself readily, so pick up what falls unless you want them everywhere next season.
Knowing when to pick
The husk is the indicator. A tomatillo is ready when the fruit has filled the husk and split it, and the husk has turned from green to papery tan. The fruit underneath should still be firm and green.
Left longer they turn yellow and go sweet, which loses the sourness that is the whole point. For salsa, pick them green and firm.
Fruit that drops before the husk splits is usually unpollinated. Fruit still in a tight green husk is not ready.
Storing and using
They keep for weeks in their husks in a cool place, and months in the freezer husked and whole. Peel off the husk and wash off the sticky film before cooking.
For salsa verde, roast or boil them with garlic, onion and a green chilli, then blend with coriander and lime. Raw gives a sharper, brighter result; roasted is sweeter and rounder.
See also: How to Grow Tomatillos in the Plant Library for sowing months tuned to your region.