Why Is My Kale So Tough and Chewy?

Kale has a reputation for being tough, and shop-bought kale can reinforce this — large, old outer leaves stripped from a stressed commercial crop. But home-grown kale, harvested correctly and at the right moment, should be substantially more tender and pleasant than anything you can buy. If your kale is unpleasantly tough regardless of how you cook it, the leaves you are harvesting, the growing conditions, or the variety are likely the issue.

Old outer leaves are always the toughest

Kale toughens as leaves age. The oldest, largest outer leaves of a mature plant are the most fibrous and most bitter — they have had the longest time to develop thick cell walls. The young, smaller inner leaves and the leaves from the plant's growing tip are noticeably more tender and mild. Most people eating shop kale are eating the large outer leaves, which gives kale its reputation. Harvest from the growing tip downward, taking the medium-sized leaves and leaving the very largest. The central growing crown should always be left intact to produce more leaves.

Heat makes kale tougher

Kale grown and harvested in warm summer conditions is consistently tougher than autumn and winter kale. The same plant in the same location produces much more tender leaves once the temperature drops below 10°C regularly. The cold-weather conversion of starches to sugars (anthocyanin production aside) also changes the leaf texture alongside the flavour. If you can only harvest your kale in summer, this is the main reason it is tougher than expected. Wait for the cold weather and taste the difference.

The central rib is always tougher than the leaf

Even in very tender young kale, the central rib and the thick mid-vein are tough and fibrous compared to the leaf lamina (the flat green part). Removing the rib by folding the leaf in half and tearing or cutting along it makes even mature kale leaves dramatically more tender. On younger, smaller leaves, the rib is thin enough to eat; on larger leaves, removing it before cooking or eating raw is worth the few seconds it takes.

Preparation transforms tough kale

Massaging raw kale with olive oil and a little salt or lemon juice for 2–3 minutes physically breaks down the cell walls and releases liquid from the leaves, making them noticeably more tender for salads. For cooked kale, briefly blanching in boiling salted water for 30–60 seconds before sautéing or stir-frying softens the texture significantly. Braising kale slowly in liquid — stock, wine or water — produces the most tender result of all, fully breaking down the fibrous texture in 10–15 minutes.