Some oriental brassicas are prone to aphid infestation. You need to order
lady beetles and later lacewing larvae for these pests. White fly can be a
problem, rarely, though they are more of a problem with bedding plants such
as tomatoes, peppers, eggplants, etc. Encarsia formosa must be introducted
for effective biological control of whitefly, though the lady beetles and
lacewing larvae will help.
If you plan to begin crops immediately, I suggest that you order a few quarts
of lady beetles to hold in your greenhouse refrigerator. Release them as the
aphids appear. You can also introduce various calchid and bracanid wasps
from the wild, but this requires an existing aphid population. Otherwise, you
could prematurely introduce aphids! Small flowers such alyssum greatly extend
the benefits of such wasps as they are parasitic only in their larval stages
and live 10 times as long as adults, laying 10 times as many egges, if pollen
and nectar are available.
I do not recommend that you continue with Oriental brassicas, except possibly
kyona, after the weather becomes warm enough to grow them outdoors. During
this season, eggplants, peppers (capsicum) and water spinach make excellent
greenhouse food crops until the next fall.
I hope that this information is helpful. I have considerable experience in
managing organic greenhouses successfully. Please contact us if you feel the
need for detailed consulting. You might also see if you can find in the
university library a copy of a publication that sounds something like
"Horticultural Management of Solar Greenhouses in the Northeast," by Miranda
Smith et al. This is based on work done by the now-defunct New Alchemy
Institute. You may have some of their journals and/or newsletters in your
library. The journals, in particular, are reliable as far as they go.
Miranda got a lot of her organic greenhouse experience at NAI. We are
moving and that portion of my library is already in storage. Sorry.
For Mother Earth, Dan Hemenway, Yankee Permaculture Publications (since
1982), Elfin Permaculture workshops, lectures, Permaculture Design Courses,
consulting and permaculture designs (since 1981), now offering by email a
Permaculture Design Correspondence Course. Copyright, 1996, Dan & Cynthia
Hemenway. P.O. Box 2052, Ocala FL 34478 USA. YankeePerm@aol.com
We don't have time to rush.