The short answer: yep! If you’re using it as on your body, it’s actually easier to handle something that’s more like a salve than a liquid. If you’re spraying it on plants, just let it heat up in a pan of warm but not hot water. Do not microwave – heat destroys some of the active compounds.
The longer answer: neem oil contains high levels of essential fatty acids (the topic of an upcoming blog) that begin to solidify when temperatures drop below about 76 degrees. The fatty acids have significant benefits for skin but they’re also good for the neem oil itself because it helps keep it from going rancid.
Depending upon how cold it gets how fast, neem oil may solidify in different layers and at different levels of hardness. That’s because it contains different compounds that solidify at different rates. The gunk at the bottom of the bottle may look bad but it’s actually my favorite part of the oil. There’s no solid reason – pun intended – just an intuition that it’s the really good stuff.
Fatty Acids Help Protect Against Rancidity
And speaking of rancidity: that’s a regular question too. Those long-chain fatty acids that cause it to solidify also make it less likely to turn rancid than other oils. We have a friend who had been in the neem business when we first started in 1992. When her husband died, she found a 55-barrel of oil in a shed that she estimated to be about 10 years old. She called us to find out what we thought she should do with it.
I don’t know that I would have recommended it for human use (since the shed was in Florida where high temperatures could break it down) but I told her to check the smell. It wasn’t solid and smelled just like we would have expected, and so she tried it on her plants. It was just as effective. In fact, she had so much that she shared it with master gardeners who also said it worked as well as anything else.
(Yes, we know neem smells funny even when it’s totally fresh, but rancid is a totally different scent. The only time it’s ever been a problem here was when we used an old towel to clean some neem oil up and then washed it with newer towels. It was a very distinct odor and very recognizable as different from the smell of standard neem oil.)