I'd use the Neem oil on the plant and the soil. It should say on the bottle if it's concentrated or ready for use. If you're not sure, dilute it and repeat spraying it every few days for up to a week. It should work.
I came here to tell my greenhouse is still surprising me. I walked in yesterday to a couple of three to four inch Calendula flower heads blooming and have small tomatoes still producing. There's no heat in there but the temp was 52 degrees with no sun. The kale and lettuce looks wonderful and the broccoli is still putting out small heads. Amazing how all the herbs are still flourishing too. parsley, thyme, rosemary, sage, lavender, etc. Oh.. also have a lemon tree still out there with two to three inches of new growth. That I may bring in the house if the temps drop further. I wanted to get some pictures before I wrote this but haven't done so yet.