1. Basil on window sill? Do you realise just how big basil can get? Two people, arms outstretched, hands joined, could just about give a mature basil a hug. Three 10yos could just about do it, but they wouldn't be able to see each other over the top of the plant.

2. Large plants means large root systems means can't survive in small pots that fit on window sills. Those roots have nowhere to go when they grow - except straight to heaven along with the rest of the plant.

3. Glass in window gets hot enough to burn both hands and plants. Glass also filters out certain of the sun's rays which plants need to survive.

4. Plants in kitchens get covered in gunk (check the top of your cupboards if you don't believe me), so can't breathe, and are exposed to large fluctuations in temperature. A recipe for death.

5. Plants on window sills sit in a saucer which holds water, yes? Roots of said plants quickly get wet, stay wet and rot. Plant gets very sick and dies.

6. Unhappy, squashed and starved roots=very sick plant=very susceptible to bug attack.

Solution:
Take plant outside, plant it in the garden or a very large pot, and pray a lot. It will look dreadful for a week or two while it recovers from its transplant operation, but if it's going to survive your oncoming winter (doubtful) it will sit up and take notice after a week or so.

Basil is an annual, and is pretty much guaranteed to die over winter anyway. Even if you live in a warm climate.

Think basil - think summer.

hi Paul.. the above comment can be very true, however, if your living in a city and have no outdoor space, like me, then we grow on our window sill :) Actually what I do is place my basil on a small table just near a window.

My Basil is from seeds planted in May and they are still growing in their small terra cotta pots.. just be sure that your pot drains well. And at least once a week(on the really nice days) I open the windows or take it out to my sun porch where my other herbs currently are.

To help with your infestation, you may want to think about purchasing an insect killer spray. Or if you prefer organic you can always google how to make your own..there's a ton of websites that can give you instructions.. or stick with your current method if it seems to be working.

Imho, I think you should re pot it in different soil. If you cannot get your finger an inch or so in then the soil may be too dense. You can buy just a little bag of good draining potting soil, or maybe you can ammend the soil you currently have with some sand and/or sphagnum moss. And go ahead and pinch those yellow leaves off.

I wouldn't fertilize especially with it so late in the season. And make sure to freeze or dry some of your leaves before you've squeezed all the life of your plant that you can lol.. but I like to do this so that I can still enjoy the herb even in the cold cold months.

But as I read over my advice I'm reminded that it is almost October so don't go and spend too much money and/or time as my indoor basil usually is a goner by the end of November.

Good luck and remember "Nothing ventured, nothing gained!"

There many dozens of basil types and only a few are small at a foot tall and bushy, with small leaves. I grew a mammoth basil that had 12 inch diameter leaves and was over 5 foot tall. I seriously doubt if any kind of basil will grow very well indoors in pots. Even for that, sunlight is very necessary for at least 8-10 hours per day. Artifical plant lights would require being left on for over 20 hours per day. If you do insist on adding fertilizer, I suggest the Herbs Alive from Gardens Alive, which is slow release and helps to improve flavors of most all herb types. It contains no nasty chemicals.

A windowsill is fine. I like using window boxes. They fit right along a windowsill and give herbs a good amount of root space.

As long as the window gets enough light throughout the day (5-8 hours) they will be relatively happy. Don't worry about it getting too big, basil only gets huge if grown outdoors.

I have basil plants that I started from seed last October 2008. Carried over inside and repotted them late spring. I still have them growing now and will likely carry one or two over this winter. They do love warm 60-90 weather. They can be grown in a small pot as do bonsai trees but there is more care involved. Don't invest too much into it but keep going. I would consider repotting it to a looser better draining potting media. They are not easy to get thru winter but it can be done with attention to sun, water and light fertilizing.
Happy Growing David
BTW carried over winter in 2 inch square flat of 20. They didn't look great and I lost a few by March but the proof is in the pudding as they say because I am still eating from them a year from the start of these seed!

Paul - you don't say where you live. Daisy's experience is in the sub tropics but a basil bush would be a dream for me. I have to grow it new every year and I keep it under glass even in high summer because our weather is just too cool and wet for it to really be happy outdoors. I grow it in a 1 foot diameter terracotta pot and sow it quite thickly. I then harvest it as a cut and come again crop rather than a single large plant. I find that late October/November is pretty much the end of the basil season for me. I've tried taking into a warmer room but then it has insufficient light. Unless you are going to faff with grow lights etc I'd treat basil as a seasonal delicacy. Just look forward to next year's basil season. Luckiy it is ready just when the tomatoes come in again.

If your basil gets a little pale looking the secret to greening them up is a very little bit of epsom salts dissolved in water and watered into the plant - not very often though - only when the colour starts to fade. Bottom water and use weak solution of fish fertilizer also.
I found the best solution to bugs is Safer's (I grow as organic) Basil likes lots of room for the roots to spread.
Good luck

I think the key is to make sure the basil is in a container or soil that will drain very easily. And the more light the better.

Are all varieties of basil annuals? I was hoping the one I brought inside in a pot would live through the winter at least but it looks awful!

I start basil under lights, and start eating it when the plants are 2-3" tall. One of my favorites is Holy Basil, and the ones with very small leaves, some of which make nice ball-shaped small plants. One pack of seed may have 100 seeds = 100 plants, so just growing them in succession as needed is not expensive.

Basil grows great in my aquaponics system. I have a 40 gallon stock tank with shubunkin goldfish, and pump the water into a gravel grow bed. It fills and then a siphon kicks in and drains the bed. I have artificial light but it's by a western window so gets a little sunlight.

As for the lower leaves dying off, most plants will do that as they grow. So for a plant like basil I would eat the lowest leaves first while they are still appetizing.:-P