Determining if tomatillos are ripe

Subject says all. There are a couple different varieties. I have the classic small green type, a similar sized purple type (called conveniently "Purple") and a large green type that gives a fruit about the size of a beef tomato. Most, but not all, are in a greenhouse (I am near Uppsala, Sweden). For now temperature in greenhouse is holding between 20-30 degrees C, but maybe not much longer, at least at night.
I cross-pollinated with a brush a couple weekends ago (bees did not pay much attention to the plants, butterflies a little more). There are now obvious signs of fruit. I wish to obtain seeds for next season, as this is my first effort. That is all relvevant info I can think of.
Any suggestions on how to determine when tomatillos will be ripe? Other suggestions, like fertilizers, are welcome (plants look healthy for now).
Dominic
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Wed, 10 Aug 2005 18:31:14 +0200, Dominic-Luc Webb

This does not sound good. Tomatoes are self pollinating and to get the same strain a "sock" (well, panty hose) should be placed over the developing flower whose seeds you wish to keep. Do not let it cross with other types of tomatoes.
If the air is still, flick the flowers gently over several days to make pollen fall and fertilise the flower. The brush will work, but it is hard to prevent cross-pollination on the ones you wish to keep the seeds. -- Gardening Zones Canada Zone 5a United States Zone 3a Near Ottawa, Ontario
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Jim Carter wrote:

Tomatillo plants are self-sterile. You need at least 2 plants to get any fruit. (it surprised me the first year I tried to grow one)
But for OP's question, just pick up fallen tomatilloes at the the end of the season for seeds. (you will probably have thousands of volunteer plants next year anyway)
Bob
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks bunches Jim Carter and zxcvbob!
Your combined remarks left me a bit confused (I am certainly no expert). On the one hand, Jim is claiming that tomato (presumably it is same for tomatillo) is "self-pollinating". On the other, zxcvbob says they are "self-sterile". These seem diametrically opposed. My understanding (maybe wrong?) was that pretty much all plants in the tomato/tomatillo family (many different food plants) must be cross- pollinated. To me, this means at least two plants of same variety are needed. Pollen from plant #1 pollinates plant #2, but plant #1 cannot pollinate itself, etc. Am I missing something?
Within similar discussion, reading up lately on bees, I learned that many plants are wind-pollinated or that bees cannot access the nectar or the nectar is not of a type interesting to the bees, so other insects end up pollinating the flowers. Other times, there is simply the matter that bees already found plenty of nectar from other nearby flowers and have tendency to stop exploratory behavior once they find a plentiful source they are happy with. In many such cases, insect pollination is not critical. Upon examining my tomatillos more closely, like when trying to cross-pollinate with a brush, I found that the pollen is quite small and easily made airborn, suggesting wind pollination is possible. The pollen is readily accessible due to the flower geometry, but bees mainly ignore the flowers. Other insects, especially some butterflies, have thus far spent considerably more time actually landing on the flowers and accessing nectar. Interesting point, there were a number of bee exploratory events, but it was clear they were not actually stopping, landing and accessing nectar. So the question comes up, what are typically the dominant mechanisms for tomatillo pollination?
Finally, nomenclature question. When I say "cross-pollinate", I am meaning crossing two separate plants with separate roots, stems, etc, but exact same variety of tomatillo. Is this correct terminology? I presume if crossing with different varieties, one would say they are hybrizing or some such. Not sure about these details.
I have already asked a few questions. I'll stop here.
Dominic
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Check this site out. http://www.floridata.com/main_fr.cfm?state=ref_contents&viewsrc=lists/contents.cfm
--
Susan N.

"Moral indignation is in most cases two percent moral, 48 percent indignation,
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.