Tomatillo

Physalis ixocarpa

Introduction: The tomatillo has been grown in Central America for around 3000 years, but it is often as much a weed of cultivated fields as it is a crop. In this country it is commonly found in parts of the country with large Latino populations, but is becoming increasingly popular in other areas too.

Tomatillo means small tomato, and was presumably given because it is a relative, though it is quite a bit different. It does have fairly similar cultivation requirements, though it is somewhat more independent.

This species is sometimes called the husk tomato because of the papery lantern (actually a calyx) that surrounds the fruit.

Nutritional content: The fruit contains vitamins C and K as well as copper, iron, magnesium, manganese, phosphorus, potassium. It is also rich in niacin and folate.

The fruits contain about 150 calories per pound, which is quite a bit more than the tomato.

Crop use: The tomatillo is a pretty easy plant to grow and can be quite productive for the amount of work it requires (which isn’t much). It isn’t very important from a nutritional standpoint, but does have some culinary interest.

Ease of growing: In suitably warm climates tomatillo is very easy to grow; in fact it often volunteers and grows itself like a wild plant.

Climate: The tomatillo is a sub-tropical plant and does best in a warm, humid climate (it will happily tolerate temperatures in the 90˝s °F). However I have also read reports of it growing and producing well in cool, wet England, so it is obviously more adaptable than we usually give it credit for.

About Tomatillo   Seed facts Germ temp: 60 (65 – 70) 75°F Germ time: 5 – 14 days Days to germinate: 5 – 14 Germination %: 75 Seed viability: 4 – 7 years Weeks to grow transplants: 6 – 10   Planning facts Hardiness: Tender Growing temp:      Day: 65 (70 – 85°F) 90      Night: 55 to 65°F Plants per person: 2   Planting: Start: 4 – 6 wks before last frost Plant out: 2 – 4 wks after last frost Direct sow: 2 wks after last frost   Harvest facts Days to harvest: 60 – 80 from transplant Yield: 1 – 8 lb per plant Yield per sq ft: 4 oz – 1 lb

Soil

pH 6.0 – 7.0

Tomatillos aren’t as hungry as tomatoes, but will be most productive in a well-drained, moisture retentive loam, with lots of organic matter. However they will grow in almost any well-drained soil.

They don’t need a lot of nitrogen and too much can result in lots of vegetative growth and few fruits.

Soil preparation: If your soil is less than perfect the plants will benefit from the addition of 2˝ of compost or aged manure. You might also put a handful of fertilizer mix in each planting hole.

Planning

Where: These plants need the same conditions as the tomato: as much sun as possible, good air circulation and a warm sheltered site.

When: Tomatillo is usually started indoors like tomato 4 – 8 weeks before the last frost date (the length of time they take to grow will depend upon how warm they are). However if you have a long growing season, or a fast maturing variety, it is possible to direct sow them.

Planting

Planting indoors: Plant the seed in a flat 1˝ apart and ¼ – ½˝ deep (they like to be covered.) Prick them out into another flat when their first true leaves appear, spacing them 2˝ apart. You can also grow them in cell packs or soil blocks.

Harden off: Before transplanting outside you must harden the seedlings off, so they become accustomed to somewhat less than ideal conditions (see Tomato for how to do this).

Transplanting outside: Bury most of the stem when transplanting and roots will form all along its length. If the plants are very leggy you should pinch out the lower leaves before planting.

If the weather is cool at transplanting time, you can warm up the soil with cloches or black plastic.

Sowing outdoors: The seed should be planted ¼ – ½˝ deep, after the soil has warmed up. Pre-germinating the seed inside may help to speed things up.

Direct sowing these widely spaced plants isn’t a very efficient way to use precious bed space. It is much better to start the seeds in a nursery bed and only plant them out when they are good sized transplants.

Spacing: Tomatillo plants can get quite big, so space them 24 – 36˝ apart each way.

Support: These tend to be quite sprawling plants and some people grow them in tomato cages to keep them under control. If you have space its easier to let them run wild at the edge of the garden.

Care

Generally tomatillos are independent, almost weed-like plants and don’t need a lot of attention.

Water: Tomatillos are quite drought tolerant, but will be much more productive if watered regularly.

Fertilization: If your soil isn’t very fertile, give them a feed of compost tea or liquid kelp when the flowers first appear.

Mulch: This is helpful to conserve moisture and keep down weeds.

Control: The tomatillo is a sprawling vigorous plant and in the right climate it can really spread. When a stem touches the ground it will commonly root, so you can easily end up with a jungle of tomatillo. Avoid having it root where you don’t want it to by moving the growing shoots promptly.

Frost: You can extend you harvest season by protecting the plants from early fall frosts. Cover them with fleece frost blankets/row covers, or whatever you have available (cardboard, bed sheets, a layer of straw).

Problems

Pests: Tomatillos have a lot of potential enemies in the form of hornworms, fleas beetles, cucumber beetles, Colorado potato beetle, aphids, nematodes, stink bugs and more. However I have found them to be relatively untroubled.

Disease: Tomatillos are attacked by the same diseases as tomatoes, but aren’t usually as susceptible. These include early and late blights, anthracnose, mosaic virus, southern bacterial, verticillium and fusarium wilts and of course damping off (which can infect almost anything). Powdery mildew is a common problem where air circulation is poor (as always).

Harvesting

The fruits are ready to harvest one to two months after flowering (depending upon the variety). When the fruit is ripe the husk will turn yellow (or purple or brown) and will be completely filled by the fruit (to the point where it often splits open.)

Tomatillos will ripen off the plant, so you can pick the fruit while it is still green (so long as it fills the husk). Some people say slightly unripe fruit is actually better for salsa.

You will often find ripe fruit in their papery husk, sitting on the ground. These are still edible and will stay good to eat for quite a while.

Storage: The fruit can be kept for a couple of weeks at room temperature, sitting in their husks. They can also be made into salsa and canned. You can freeze the puree as you would that from tomatoes.

Seed saving: Just remove the seeds from the ripe fruit before you eat them and process as for tomato. The fruit is more variable however, so save seed from the best flavored plants. I have always believed tomatillos to be self-pollinating like tomatoes, however when I looked online I found many sites claiming that they are self-incompatible and needing cross pollination (the internet nearly always provides contradictory information, so this wasn’t a big help). As it makes sense to have at least two plants anyway, this isn’t a big issue. The flowers are very attractive to bees and I have never had any problem with fruit set.

Unusual growing ideas

Volunteers: If any fruits fall to the ground and rot, you will most likely get volunteers the following year and forever after (it does this much more successfully than the tomato). These will be just as good as their parents so can be allowed to mature and bear fruit. If they like your garden you may never have to think about planting them again

(which could be a good or bad thing depending upon how much you like them.)

Dry gardening: Tomatillo is independent enough to grow without any irrigation, even in quite dry climates. They may not get as big as irrigated plants, but they will be big enough.

Dry gardening requires that the plants be spaced further apart, to give each one more root room. See Tomato for more on this.

Containers: Tomatillo does well in a container, so long as you give it good soil, plenty of water and a deep pot (it can grow to be a big plant, so a 5 gallon pot isn’t too big).

Varieties

There are only a few commonly available varieties at the moment, but new ones keep appearing.

Purple De Milpa: This is considered to be one of the best flavored. It is almost a wild plant and often volunteers.

Cisneros – Produces the biggest fruit of any common variety,

Purple – Large purple fruit for purple salsa verde (or should I say salsa morado!)

Toma Verde – Yellow green fruit.

Kitchen use

The tomatillo is important in Mexican cooking, for its use in the classic salsa verde, as well as other dishes (it’s good roasted). It is not usually eaten out of hand.

Salsa Verde   12 tomatillos 1 medium onion ½ cup clime juice 5 cloves of garlic ¼ teaspoon sugar (optional) 1 to 2 finely chopped jalapeno peppers 1 tsp salt   Chop all the ingredients and mix thoroughly in a bowl. That’s all there is to it. It is better is left overnight before eating.

Related species

Ground Cherry

Physalis peruviana

Also known as cape gooseberry, this species is a close relative of the tomatillo and is cultivated in the same way. The fruit looks like a small tomatillo, but it has a pleasant sweet/sour flavor and is good enough to be eaten raw.

Like the tomatillo the ground cherry enjoys hot weather, but it is significantly hardier and in milder areas (zone 8 and higher) it can be grown as a tender perennial. It will often survive for several years and be more productive after its first year. In areas with colder winters it must be grown as an annual though.

This species is naturalized in some areas of the country and in a few it is actually considered an invasive species. If it likes your garden it will often volunteer from fallen fruit. Once you have an established plant you it can be multiplied by taking (and rooting) soft cuttings.

Harvest: Like the tomatillo, the fruit comes wrapped in its own husk and may be picked before it is ripe. They sometimes fall from the plant before they are ripe and lay on the ground, which is presumably where the common name comes from. Unlike the tomatillo the fruit doesn’t completely fill the husk.

Kitchen use: The ripe fruit is soft, yellow and sweeter than the tomatillo, so is more commonly eaten as a dessert. They can be eaten raw, or cooked in preserves and sauces. They can also be frozen whole to preserve them.

Varieties:

Goldenberry

Giant

Yellow husk

Strawberry Ground Cherry

Physalis pruinosa

This annual is used like the above. Some people say it has better flavor.

Aunt Mollys Ground Cherry – This Polish variety is the most commonly available type. It produces small sweet fruit.

Goldie – Has bigger fruit.

Golden Ground Cherry

P. pubescens

Another annual that is used like the above.

Cossack Pineapple – An Eastern European variety.