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neat lavender essential oil (again!) for minor burns (e.g. on hand from hot oven, iron etc.) - cool area for few mins first with cold water, then when completely cool apply a few drops of neat EO. Often completely prevents blistering - magic!

To treat mouth ulcers. Make a gargle using two teaspoons of coriander seeds boiled in water. Once cooled, strain and use the gargle 3-4 times a day.

Eating fresh pineapple helps to clear mouth ulcers, it's the bromelaine in it that does the business.

42. feverfew for head aches best eaten in a tomatoe sandwich
43. inside banana skin fot insect bites
44. tea tree fot vercua
45. elderberries for colds

Re mouth ulcers.
Speaking for myself, I always get them when I lack zinc. So though you can deal with them in many ways, to prevent getting them it's good to eat more shellfish (oysters!), peas/beans, yoghurt, (pea)nuts, whole grains and seeds.
Meat eaters are less likely to get a deficiency, as it's plentiful in liver and red meat.

Garlic tablets for colds etc.Before I met my OH,he used to get regular colds.My herbalist mate told me years ago to take two garlic tablets per day,everyday which wards off any bugs.I haven't had a cold for 25 years!I put my OH onto them when we first met and he hasn't had a cold for the 12 years I've known him lol.

Can blackcurrant leaves be used as a remedy for something?

Seems to be used for urinary tract infections and rheumatism.

You can make tea with them, but I don't know what it tastes like. As ina says, it's associated with urinary tract can have a diuretic effect.