Here’s an extract from our lovely book by Caroline Aitken and Martin Crawford

Day lilies (Hemerocallis spp.)
There are several species and hundreds of varieties of Hemerocallis – grassy-leaved plants that grow in any soil or situation. Day lilies are widely used as garden flowering plants, and the large bright flowers are a fine vegetable crop, containing useful quantities of vitamin C, potassium and phosphorus. Unlike most edible flowers, they are really substantial: thick-petalled and crunchy, with a delightfully perfumed and mildly peppery flavour, which can be used in soups, salads and vegetable dishes.
The bright peach-orange colour of the flowers makes them decorative as well as tasty, and when cooked they add a subtle yellow tinge to the dish they are added to. They can also be enjoyed as a side dish, sautéd in a little butter or fried in a light crispy batter. The older flowers that are beginning to wilt are said to have the strongest flavour, but the unopened buds and fresh, opened flowers hold their shape better if being used whole. The unopened flower buds taste rather like green beans.
Harvest flower buds early in the morning before they open, and flowers towards the end of the day. The previous day’s withered flowers can also be picked and dried for seasoning.

80g (23/4oz) day lily flowers, finely chopped
30g (1oz) butter
1 tbsp olive oil
1 medium onion, finely chopped
2 celery sticks, chopped
300g (101/2oz) courgettes, diced
2 garlic cloves, crushed
200g (7oz) potatoes, diced
1l (13/4 pints / 35fl oz) vegetable stock
Salt and pepper
Garnish:
Crème fraîche or yogurt
Stick blender

Melt the butter in a large saucepan over a low heat and combine with the olive oil.

Add the onion, celery and courgettes and fry over a medium heat for about 3 minutes until soft.

Add the garlic and fry for a further 2 minutes.

Add the potatoes and stock, cover the pan and bring to the boil.

Reduce to a simmer and cook for 10 minutes.

Add the day lilies and cook for a further 5 minutes. Remove from the heat and blend until smooth, using a stick blender.

Season to taste and return to heat. Bring the soup just up to boiling, remove from the heat and serve. Serve with a little crème fraîche or yogurt.