what temperatures are too cold to ship orchids

[cirillonb]

now that it is colder (around here freezing at night and low 40's during the day) but not frigid, as below 10 deg., is it safe to order orchids that are shipped by Postal Service or UPS?
Are the hot packs offered worth the price?
Nick

[lambelkip]

it's generally safe to order, but definitely get the heat packs. 2 or 3 days in near freezing weather will almost certainly damage the plants, if not kill them. what type of orchids are you ordering?

[Ray]

Don't forget that some plants are more tolerant of temperature extremes than others, but generally, plants should ordinarily not see below about 50° to be safe, but if they are dry, they can sometimes take maybe 40° for a brief while.

Yes, heat packs are effective, but they must be used in conjunction with insulation, and there are some things to deal with when using them. My approach, for example, is to surround plants with shredded paper, wrap them in closed cell foam, and wrap THAT in sheets of kraft paper or newspaper. Then I line the box with the closed cell foam, and surround the wrapped plants with foam peanuts. Just before shipping the package, I add a heat pack or two, and away it goes.

Back to the heat packs themselves... 1) They have a limited life. I use 60-hour packs, but ship for 2-day delivery at most. 2) You cannot seal the box, or the pack will consume the oxygen in the box and stop working. 3) moisture is also a prerequisite for them working, so if I'm shipping in really dry weather I'll throw a wet paper towel in the box to increase the humidity.

[lambelkip]

good info, ray. i hadn't heard about them consuming oxygen. all of the orders i've placed came in a sealed box, with the pack still warm. it would be an interesting experiment to see what size of a box contains enough oxygen to keep it going, and what conditions the pack can keep it warm in.

[cirillonb]

thanks Ray. I guess it is important to know the grower or at least communicate with them regarding their specific mailing techniques.
Nick

[dounoharm]

yes its worth the heat pack expense to be able to feed your need for the elusive orchid during colder months....its so hard to wait till spring! get the heat pack and be happy!

[CoolPhrog]

Ray, I have a question. If you say you can't seal the box for concern of the heat pack using up the oxygen, how then do you ship? I'm confused...

[Ray]

I don't seal the boxes totally. A typical cardboard box has openings at the corners and sometimes at the seams - just don't tape them closed. If it looks tight, poking a few holes in the box is adequate.

Those heat packs are basically iron filings, graphite, and salt. Upon exposure to oxygen and humidity, the iron rusts, which is an exothermic reaction. The carbon is a time extender.

[tmaxwell]

I just received seedlings today, 10 of them, shipped usps. No heat pack, and it's below freezing in the day, 10-15 at night. No problems! But, the mail handler here is responsible, and heeds the "live plants, protect from heat and cold" on the box. If done right, the plants just aren't exposed for very long.

[camille1585]

Originally Posted by tmaxwell

I just received seedlings today, 10 of them, shipped usps. No heat pack, and it's below freezing in the day, 10-15 at night. No problems! But, the mail handler here is responsible, and heeds the "live plants, protect from heat and cold" on the box. If done right, the plants just aren't exposed for very long.

Wow, you're lucky to have mail people that actually read the boxes! I don't trust them anymore after a particularily bad handling of a package. I was waiting for a package with meds for my allergy treatment, and they must be kept refrigerated (written very big on the box). Since no one was home they left a note saying to pick it up at the post office in 3 days (a dumb rule). This was the middle of summer mind you, no air conditioning, and when I went to get it it was on a shelf by a window....in full sun. Their explanation? They didn't know!! How dumb!

If they can't be trusted withs meds, they sure aren't touching my orchids in the winter, heat pack or not! The "come get it in 3 days" rule is ridiculous, that's what happened to a box of orchids in May. Boy were they thirsty!