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Re: How cold is too cold?

>Ok, now that we've addressed the tomato staking/spacing issues, can anyone
>tell me how cold is too cold for tomatoes?  I've set out a few babies, and
>believe I have them hardened down to about 45degrees, but is that possible?
>Also basil and peppers, are they susceptible to chill?  How about on very
>windy days (like today)?  Any ideas appreciated!

While you *might* be technically able to harden off your tomato plants to
the point where 45 degrees F. wouldn't kill them, they will make about zero
growth at that temperature.  Cold soil just takes the life-spark right out
of toms.  They'll hang on in misery for a week or more but won't do any
growing.  I suspect, in fact, that their later development would be severely
held back by an early jolt like the one you describe.

Now Wall-o-Waters will keep the ambient (air) temp around a young tomato
plant high enough overnight to protect its above-ground parts from frost
damage fairly well.  But WoW's don't affect the soil temp, and that's what
shocks toms into submission.

The soil temp thang is why most outplanting instructions for tomatoes say to
put them in 2 weeks after your last frost date.  By that time, enough solar
energy has probably been absorbed by your soil to make it genuinely
hospitable for tomatoes and eggplants.  I know nothing about basil, but I
suspect peppers are just as cold-sensitive as tomatoes and eggplants.

Windy days are a threat to plants on several fronts.  For one thing, wind
encourages plants to transpire moisture.  If the ground is dry or they're
newly planted and have little effective root structure with which to draw up
soil moisture, windy days lead right to desiccation.  I'm always startled at
how quickly this can happen to my rhododendrons in the winter.

For another thing, if your plants are not solidly rooted in their permanent
homes, wind gusts can just topple the plants over, exposing rootlets and
very likely killing the plants outright.

There's a kernel of basic truth about March--in like a lion, out like a
lamb.  Waiting until later in the month to move foward with this season's
gardening activities is probably good advice almost everywhere in temperate
North America.

--Janet


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Janet Wintermute             jwintermute@ids2.idsonline.com
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