Under Attack

I've had a lot of failures lately.  Many of the crops I planted in my big containers have stalled or just died.  I'd say it's a combination of constantly wet soil and the high temps...which cause population explosions of RKN, root knot nematode.

I thought fallowing and crop rotation might cure these problems, and I went to great lengths to fallow all my potting soil for at least a month before reusing it.  But it didn't work.  The RKN is attacking almost everything, even vegetable amaranth and mustard, which I thought were resistant to it.  I found an enormous root knot on one of my crop plants when I pulled it, the biggest one I'd ever seen.

So new tactics are called for, so I'm going all-out with onions. RKN can't live on onion roots and I do enjoy green onion in my soups and stir fries.  And I'll probably switch my efforts to planting beds, which are generally drier if well drained.  The South Garden is overrun with invasive grasses, which are also immune to RKN.

So...onions in the containers, and everything else in the planting beds for a while.  PPN problems (plant-parasitic nematodes) are a huge problem in tropical and subtropical gardens.  In northern gardens, there are one or two species of PPN.  Here in Florida we have over a dozen at least.  And we don't have cold temps to kill them off every year.  They survive year-round in our warm, sandy soils.  Most likely the original problem was in trying to grow a garden in burned-out farmland.  PPN can linger in abandoned farmland for 20 years or more.

I've got about a half a pack of onion seed planted in a 12 cm pot, watching it every day for signs of sprouts...only a few so far.  It's hard to germinate onion seed at this time of year, it's probably just too hot for the seedlings.  Next I'll try indoor germination with vermiculite instead of potting soil.  That often works much better in warm conditions, fewer disease organisms in vermiculite.

Nothing easy about gardening in Florida, that's been my experience.  It takes patience and determination for success. Failing that, being bonehead stubborn also works.