Late winter and early spring is a great time to start seedlings and get the
gardening season underway. Growing your own seedlings from seed is highly
rewarding and can open doors to even more species that are not often found
in garden centers.
However, a couple of problems can sometimes curb the
indoor green thumb and seriously affect the success of growing seedlings.
Fungus gnats and damping-off are two afflictions that commonly affect
gardeners. But before you spend money on expensive chemicals, the
solution to these problems may actually be much more low cost that you
suspect.
FUNGUS GNATS
These tiny, black insects seem innocuous enough as they buzz over your
plants. While the adults rarely cause any problems to plants, if the young
larvae are in large numbers, they can damage your seedlings. Fungus gnats
search out moist soil in which to lay their eggs. When the eggs hatch, the
larvae will feed on the roots of your plants.
Healthy seedlings will often
be able to withstand this feeding but any seedlings that have small root
systems like onions and leeks and those that are showing symptoms of
nutrient stress can be put back quite significantly.
The easiest way to prevent fungus gnats is to water your plants properly.
Overwatering, which causes your potting mix to remain moist for extended
periods of time, seems to attract fungus gnats. If your plants are already
infected, allow the soil to dry out between watering. Alternatively,
sprinkle a ¼ inch of sand on top of your soil to confuse the adults. Since the
sand drains water quickly, it can sometimes trick the adults into thinking
the soil is dry.
Potting mixes containing peat seem to be particularly affected by fungus
gnats. If the problem is reoccurring for you, think about switching from a
peat-based mix to one that only contains perlite and vermiculite. Lastly, if
the adult fungus gnats are bothersome, trap them by making your own sticky trap.
The adults are attracted to the color yellow. Make your own sticky
trap by smearing Vaseline or Tanglefoot on a yellow surface and hang it up
close to where the adults congregate.
DAMPING-OFF
Not only will controlling your watering help to prevent fungus gnats, it
will prevent the second most common problem, damping-off. This condition is
caused by several fungi such as Phtophtora and Pythium. These fungi live at
the soil line, just where air meets the moist soil surface.
When your potting soil is kept continuously moist by overwatering, the fungi attack
your seedlings. The telltale symptom is a constricted stem, just at or below
the soil surface. Once seedlings are infected, they tend to fall over at the
soil line.
As mentioned, allowing the soil surface to dry out will go a long way in
preventing this problem. If, for some reason, your potting mix remains wet
for an extended period of time, look to your kitchen cabinet to help prevent
the disease. Cinnamon powder is a natural fungicide and has been shown to be
particularly effective against damping-off. In addition, weak Chamomile tea
(after it has cooled) is another natural fungicide.
Ensuring seedling success need not be complicated or expensive. Controlling
your watering and a few home made remedies will go a long way to
guaranteeing healthy seedlings.
Arzeena Hamir is an agronomist and garden writer based in Vancouver, BC. She has a Master's Degree in
Agriculture and specializes in organic vegetable gardening. She frequently writes articles for websites: Suite101,
GardenGuides and ICanGarden. When not tending her own veggie
patch, she runs Terra Viva Organics.
go to Terra Viva Organics now !
