i.e. the loose-structured soil kee is the rrountl heat But the lettuce croi under the double layer of in-
’* from rising. ner plastic dtd not brown at all. \\'hen tt was cut, it
gg? lluring extremely cold weather, limmert found the brought from $2 to $3 a basket according to the pre-
lettuce did not grow. But when warm spells and railing market.
V ~ * thaws occurred, it did grow. `l`his led him to conclude V _ `
it __ that, on the basis of early trials, vegetable production ~,_ " .
may be commercially possible and profitable up to  ,\  
  as late as (lhristmas and could start as early in the VV , /V‘ ; V   ‘V
'• · "s irin   as February l·1. .»\nd this was his aim: Ve ·e- V   .; ·’V“?{§ l " V
. 4-·, .. ,   V. Vs
table production when produce is in very short sup-   kg   V --——; V
. . . I lx   ' 7/ V} , ’
E" ily on the lll2ll`li€[—2\ll(l `rown without the cost of / gg.-   {"··.- ~- - VV / /; \ ’
Q, k artificial heat. JL .   V \ V \
r · · · T " .‘<“···*`*‘ l ` W 1
, lhe extra sheet of Jlastic over the round cover    l —Z¤* ",. `• #`· 2 l  -.. . ‘ #~
:§l¤\%("* · Kg) I- - V . :_TT1 ¤§¢*‘ [
-__ . . 1 i , _ i / ~· ’ :. , ':
;‘ was added to insure t ll2ll1l' and to hel) the cron ".9l*‘ - - ‘ ~‘ `  yi;)/’>°W} · `
- lh '; "@°@f‘ »   #- *~·»*·..~- i
..,'_.‘ grow. Lettuce grown without the aid of any inner ‘ “ ’ ` W     ·_\ ·
ilastic rround cover browned u J c uickl t and lost
· ‘ . .
?V*" quality when it did grow. Under- ;t single luygy of This sketch (not to scale) shows the essential elements of the
VV_ · %_mil l)luSLiCV the lcuucc grew but had U tendency LO plastic greenhouse within a plastic greenhouse. lt is ietom-
I _ V _ V ._l V _ _[V` V N . I _ __ M I mended that the height be about (1 feet. each side of the
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The lettuce grown in this plastic field greenhouse was mar- aisle to permit access and the plastic on each side, supported _
keted when produce was in short supply. Note the center by wire frames.
  7
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