over wintering

[garyhove]

I would like to know what powders or chemicals people use for over wintering their bulbs?

Also is flowers of sulphur the same as sulphur?

[Frans IJsselstijn]

Hello

I never use powders or chemicals for dormand orchids tubers
What kind of orchids you have for over wintering.
Some have to keep dry when they are dormand, some a little moist.
But you don't have to use chemicals

Frans

[Maren]

I treat my pleione pseudobulbs soon after harvesting with a spraying oil to protect them from the brevipalpus mite. Later in the winter I may apply some fungicide, depending on conditions. I haven't needed to do this since I installed a de-humidifier in my pleione store.

[Slug Killer]

Same here, I use spraying oil and then let them dry off before putting them in paper bags, boxed in the garage.

Touch wood and fingers crossed I have never had the need to use any fungicide.

[karel_t]

I use Neem oil and Physan 20 on the day I repot them.
K.

[garyhove]

What is spraying oil?

[SteveC2]

And where can an amateur grower get it?  I understand that Neem oil is for the pro's only, is it the same with this?

[Maren]

Spraying oil is a generic name for oil based products used in horticulture. Their function is to encase pests in a coat of oil and suffocate them, rather than poisoning them. The effect is the same on the pest, but less harmful to the bystander.

There are a number of spraying oils, Neem oil is the best known, but other products are available from  hydroponics suppliers. Neem oil is not permitted in the UK as a pesticide, even for professionals, due to a lack of a license from the relevant government department (DEFRA in the UK). However, I have been informed by them that it is allowed as a cosmetic. Therefore, I use it as a cosmetic  'leafshine'.

You may find Neem oil for sale on the internet or in Indian shops. The Neem tree, from which the oil is extracted, grows in India and many useful products are made from this.

The oil is diluted in cool water with a squirt of detergent to act as an emollient. You can either dip the pseudobulbs in the resultant solution or use it in a fine sprayer, making sure that they dry quickly (lay them on newspaper and, a day later, roll them about a bit, so that all surfaces are exposed to the air). If left soaking in cold temperatures, you could do more harm than good. - By the way, the oil smells of worn football socks left in the kit bag for two weeks, but the 'perfume' disappears after a day.

[Slug Killer]

I use croptex spraying oil which is made by CERTIS but it only comes in 5ltrs. This gets diluted at 100:1(100 parts water to 1 part spraying oil) for adult plants and 200:1 on seedlings etc. If you do a quick Internet search you will find the data sheet. www.progreen.co.uk does supply it if you ask. I used to get it from Avoncrop. You need to use it up within a few days of mixing as it stinks after that.

I spray Pleione twice during the season when in leaf and also dip bulbs and then let them dry when dormant.

Also very effective at getting rid of some scale type insect which I found all over several Acers last year.

http://www.certiseurope.co.uk/Certis.uk/English/Home/Products/Insecticides/page.aspx/721

[Maren]

Hi Dave,
that's very interesting. Where can you buy Croptex spraying oil? I googled in vain.

[Slug Killer]

Hi Maren

www.progreen.co.uk did supply but I think you need to contact them as it's not listed.

The other option is to e-mail Certis UK and ask for suppliers. I won't be needing any for a while as 5 litres diluted at 100 parts water to 1 part spraying oil will keep me going for years.

I must stress though only mix enough for the current application and then dispose of any left over. Failure to do so will leave your sprayer with a very nasty stink when you come to empty it. Always a good idea to rinse the nozzle through with clean water anyway.

[Maren]

Dave,
thanks for the info. I shall follow that up.