What can I do about little white bugs on my cactus?
Sounds like mealy bug. Looking like tiny white slaters, these insects sometimes cover themselves with a waxy wool within which they lay their eggs - and they breed fast. If the infestation is not too bad you can pick the pests off with tweezers or a large needle, or dab on a drop of methylated spirits to kill both bug and eggs. Otherwise try puffing on a powdered insecticide, or use either a contact or systemic spray.
What's the difference between mizuna and mibuna?
Not much. Both are traditional Japanese mustard greens and members of the Brassica family. Both mizuna and mibuna have a similar growth habit and mild mustard taste, but while mizuna has feathery leaves, mibuna leaves are straight and have a slightly stronger flavour. Neither attracts white butterflies as much as cabbage or cauliflower. Plants are easily grown from seed (direct sow for best results) and soon form clumps with leaves that can be cut as needed. Good for salads and stir-fries.
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