Gardening help?

[emperor]

A while ago, we acquired a basil plant from Tesco. Remarkably, they hadn't destroyed its roots, so it lived. Accordingly, we potted it up, and put it in the newly-sorted-out greenhouse. It did well for a bit, but not it's infested with whitefly, which look to be killing it :-(

What should I do about this? I know the basil won't survive the winter, so I'm more worried about protecting the chilli plant (the only other thing in the greenhouse, and my Favourite Plant). OTOH, it would be nice to have healthy basil again. I have no qualms about deploying chemical warfare...

Comments

[hooloovoo_42]

Get some Deris from the garden centre. It's made from organic something or other and comes in a powder. Squirt it all over the plant to keep the bugs off.

If you want to get rid of the actual infestation first, get some soapy water (the old washing up water will do) and swish the plant upside down in the water to wash out all the whitefly. Make sure you hold on to the plant as well as the pot to stop it falling out. Squirting a mist of soapy water over the plants should keep the flies off, too.

[mobbsy.livejournal.com]

I've used Bayer Provado on mine (active ingredient is 0.15g/l Thiacloprid) - it warns you need to wait 2 weeks before harvesting for herbs though, and also mentions that there is widespread resistance in "glasshouse whitefly".

[juggzy.livejournal.com]

sticky backed paper flypaper?

[hooloovoo_42]

Yep. You can get yellow sticky things to hang in your greenhouse.

[keith-underdown.livejournal.com]

There's a biological control for whitefly.Can't remember its name but Google could be your friend.

[hooloovoo_42]

According to the Collins book of Pests, Diseases & Disorders of Garden plants "Encarsia formosa gives good results in daytime temperatures above 21C and is widely used in commercial horticulture". It's a parasite that lays eggs in whitefly scales.

The book also says you can use a hand held battery operated vacuum cleaner to get rid of the flies.

If you use the yellow sticky things, disturb the plant foliage regularly to maKe the flies fly upwards onto the traps (hang it above the plant).

[wellinghall.livejournal.com]

I don't know if they sell this particular biological control, but www.wigglywigglers.com have a good range of them.

[ashfae.livejournal.com]

Hmm. A really awesome trick my mother-in-law taught me for other plants is to get some soapy water (dish cleaning solution is ideal) and spray it all over the plants, and then the white/green/whatever fly poisons itself, or can't get enough purchase. Doesn't harm the plants at all, so this is brilliant. Not sure it's a good plan for something you ultimately intend to eat, though!

[arnhem.livejournal.com]

This is what we did with soap scraps when I was young, and worked very well.

I've found a very low cost, low maintenance way of doing this (as I didn't have a proper spray device).

Take a nearly empty washing-up-liquid bottle (when it's reached the point that it's too annoying to try to get any more out of it). 1/2 fill with
water and shake like mad until the other half is completely foamy. Now, with the bottle mostly-upright, squirt gently, such that a huge flume of soapy bubbles emerge.

With a little practice, you can pretty much cover all the infested surfaces with bubbly-detergent-foam. Do this a few times, and the green/white/black-fly just disappear.

Next time you need to use it, just shake like mad again. Occasionally it may need topping up with a bit of water.

Remember to keep it mostly-upright, even when getting at awkward bits.

[emperor]

This, I realise, is the down-side of having a washing-up-liquid bottle we refil from a big 5l thing we got from Daily Bread years ago!

[wellinghall.livejournal.com]

IIRC soapy water on something you will later eat is fine, as long as there's a reasonable gap between applying the water and then eating. But as teleute points out, things other than soap are a big no-no.

[teleute.livejournal.com]

Do NOT (I repeat NOT) spray it with household disinfectant/kitchen cleaner. This kills the bugs but the plant too. Guess how I know ;-)

I have no useful advice. I can only keep the plants that don't die easily. And then they do strange things like flower all year or something, which they're never supposed to do. I have an odd effect on plants.

[lnr]

We had a chilli plant on our windowsill that my dad brought us, kindly pre-infected with greenfly. We tried dipping it in the washing up water, as suggested above, but the plant died too. We never were quite sure if it was the soap that did it.

[antinomy.livejournal.com]

We had a nasty round of whitefly in the greenhouse which got to the chillies and everything else, and was eventually solved with two rounds of application of something containing Imidacloprid (which I recognise in another, veterinary, guise, and so should you!). You're allowed two applications per growing season for food crops.

In your case I recommend evicting the basil from the greenhouse, since it's nice and frost free outside anyway, before treating it. This will achieve two things - reducing the risk of infecting your chillies, and hardening off the basil plant to make it less attractive to the little blighters in the first place. I wouldn't be surprised if you ended up treating both with nasty insecticides, though, I'm afraid.