having trouble raising cabbage and broccoli from seed. I tried to
start them off in a small greenhouse, but most of the seedlings
keeled over and died. Can you advise me what I'm doing wrong?
SOUNDS as if your seedlings are succumbing to damping-off disease,
which is caused by fungal disease invading the base of the stems.
Generally, it's brought on by potting mix being too wet, especially
when other conditions for growth are not ideal, such as poor light
or low or very high temperatures.
There are several things
you can do. One is to simply raise your cabbages and broccoli seedlings
outdoors where you should have good success during all but the coldest
months of the year. Prepare the soil by digging it over and raking
so there's a layer of fine soil on the surface, or spread a layer
of seed raising mix on top of the existing soil. Make shallow grooves
with a stick, sprinkle in seeds about 1cm apart, and cover with
just a few millimetres of soil or seed raising mix. It's important
not to bury them too deeply. Put in a label to mark the spot and
If you still want to
raise them in the greenhouse here are some tips:
- Use only new or cleaned
pots and trays. You can soak them in a solution of 10ml Janola
in one litre of water for 30 minutes or so to sterilise them.
- Use fresh seed raising
mix. If older than around six months, spread it on the garden
and buy a new lot.
- Sow your seeds thinly
and only cover with a very fine layer of mix.
- Avoid overwatering.
Only water when the surface of the mix is dry to the touch.
- You could drench
newly sown seeds and young seedlings occasionally with a solution
of a general fungicide like Bravo to prevent infection.
- As soon as seedlings
are visible, expose them to as much light and fresh air as possible.
Gardener, Issue 149, 2004, Page 26
Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.