Question
QUESTION: Hi,

I have two questions about Nepenthes:

1.  A few people have recommended to me that adding a 1/4 strength solution of orchid fertilizer to the pitchers instead of applying them to the leaves is a better way to fertilize them.  They have recommended filling the pitchers 1/3 to 2/3 of the way up once every few weeks.  What do you think about this?

It makes sense to me since the pitchers were designed to absorb nutrients, but I've also heard that altering the chemical composition of the pitcher fluid this drastically could have negative effects.  I've tried it with a couple of plants and they seem to be doing well.  They also seemed to do well with foliar feeding.  :-)

2.  I have an N.sanguinea growing under lights (2 x 4' 32w T-8's with a daylight spectrum).  The problem is that when a new leaf forms, it will grow almost a foot vertically before it opens up and starts growing outwards, so if I keep the plant within a foot of the lights, the leaf will touch the bulbs.  Is there any harm and/or danger in letting the leaves touch the light bulbs?  Any tips on what to do in this situation?

Thanks!

Derrick

ANSWER: Hi Derrick,

You can certainly put the fertilizer in the pitchers of your Nepenthes, but as you've noticed, Nepenthes also grow well when you apply the fertilizer to the leaves.  For this reason, it's much simpler to apply the fertilizer to the leaves.  If you have a lot of Nepenthes like we do, placing fertilizer into the pitchers would be extremely time consuming and tedious.  

Foliar feeding isn't at all unique to carnivorous plants.  Many gardeners and orchid growers prefer foliar feeding.  Keep in mind that all plants are capable of absorbing nutrients through their leaves.  The pitchers on Nepenthes are designed to capture insects since carnivorous plants are not equipped to absorb nutrients through their roots, so the pitchers are to ensure that the plant is capable of getting some nutrients since it's unlikely that a flies would simply die and decompose directly on the leaf.

I know that Peter D'Amata recommends not placing fertilizer in the pitchers because it upsets the balance.  Here is where I disagree with Peter.  I don't understand how 1 tablespoon of 1/4-strength fertilizer is more chemically disturbing than an insect.  It sounds good on paper, but I don't see why or how it can be damaging to a Nepenthes.  From my understanding of chemistry, all it'll do is dilute the liquid and add a bit of nitrogen, potassium, phosphorous and trace minerals.  When I first started growing Nepenthes, I used to put the fertilizer in the pitchers.  I have to say that I didn't notice any adverse affects from doing so.

But the argument is moot, at least for me, since I follow the principle that spraying the fertilizer on the leaves is just as effective and a whole lot easier than pouring the fertilizer into the pitchers.

With you N. sanguinea, avoid having the tips of the new leaves touching the tube.  The intense light will damage the growing tip and may inhibit pitcher formation.  Unfortunately, the growth pattern you've described is very common when you grow plants strictly under lights without any ambient side light coming through a nearby window.

You see, the lights are consistently coming from above.  In nature, the sun moves across the sky, so light is coming from different directions throughout the day.

If possible, move the plant near a window, such as a south or west window.  The ambient sunlight coming through the side will encourage your plant to grow normally.  If this isn't possible, you may need to set up reflectors along three sides of your growing area.  You can find reflectors at many hydroponic stores.

Good growing!
Jacob Farin

---------- FOLLOW-UP ----------

QUESTION: Hi Jacob,

Thanks for the advice.

I think that for many typical at-home-growers with small Nepenthes collections, feeding the pitchers might actually be more convenient since they wouldn't have to spray diluted fertilizer inside of their homes, but maybe that's just me.  :-)

As for my N.sanguinea, it's actually growing in a northeast facing window (hence the need for supplemental lighting) with the other side of the rack covered with reflective material, so the plant should be getting light from multiple angles.  Taking a closer look at the plant, the weight of the leaves and pitchers is causing the stem to grow at a 45 degree angle, which is why the new leaves are pointing upwards when they're still rolled up.  Once they're fully developed, they'll hang outwards like regular Nepenthes leaves.  Does this still sound like unusual leaf growth?

Perhaps the best solution is to just adjust the position of the plant when the leaves are getting close to the bulbs.  That N.sanguinea is getting big fast though.  :-)

Thanks,
Derrick

Answer
Actually spraying is a lot easier and better for the plant because you don't have to risk damaging the pitchers.  The less you handle the plant, the less risk for damaged leaves and pitchers.

Yes, the weight and angle of the plant could be a factor.  Adjust the position of the plant as necessary to keep the leaves from touching the tube.  This species grows quickly, so you may need to think of a different lighting solution when the plant gets too big for the area it's in.  Otherwise, you could simply trim off the larger growth and encourage basal shoots to keep the plant compact.

Good growing!
Jacob Farin