Question
QUESTION: Ms. O'Brien,

I was given a Norfolk Pine for Christmas, and I have become very fond of it.  It was only about six inches high when I received it.  It has been growing - not much height, but lots of new branches and thicker branches and needles.  It also lost two small branches, which I've read is okay because of new growth, but they didn't turn brown first.  I'm worried about two main things:

1. My tree has five trunks!  Since it was a Christmas special from a pseudo nursery, I think they may have twisted a few trees together to look nice and full, as they sometimes do with arbovitae.  I can't determine if there are different root systems because the roots are so knotted and twisted together.  I didn't want to stress the roots by exploring and tugging.  Do I need to prune these other trunks?  They all have healthy growth, but they quite crowd each other and they're leaning.
2. The soil and pot - I asked about the potting soil, and it's supposed to retain moisture and "release" it over a week to the roots.  However, I've read about the danger of overwatering.  Should I do something about the soil?  The pot the tree is in is way too big (I think it's 9 inches, but it's very deep), but I don't want to cause too much stress by repotting it twice (once when it was gifted) in three months.  There are marbles at the bottom of the pot that help it drain, but I'm worried that the combination of a big pot and "moisture-saving soil" will drown the roots.  Also, I know conifers usually prefer acidic soil, but I'm not sure if I should do something to the soil.

I appreciate your time and expertise!  Please let me know if there's something else you need to know about the tree.

Thanks very much,

Emily

ANSWER: Hello Emily and thank you for your question.  Norfolk Island Pines (NIP for brevity's sake) often grow multiple trunks or leaders. It's a good idea to prune out the extras and have only one central trunk.
This is true even if they turned out to be multiple plants - the root competition wouldn't be good.  Just pick the straightest, nicest trunk and prune off the rest.  Don't trim off the end growth of your NIP; they get very unhappy about that.

You're absolutely right about the potting soil! I make a point to never buy the pre-mixed soil with the moisture retention granules in it. For growing my bog plants, I just add some Soil Moist to thier mix.  Ideally, the best potting soil is that which you mix yourself.  It usually turns out to be cheaper, as well.  But, that depends on how many plants you care for.  My mixes are made as needed for the requirements of the plants I'm potting up.

I agree with you, definitely re-pot the NIP in a potting mix without the moisture retention added.  NIP's aren't very picky about pH, like most conifers, and most potting mixes' pH levels are around 7.0, or neutral.  While soggy roots will kill a NIP, lack of higher air humidity will make them thrive.  The way to do this is to set the pot on a tray with pebbles in it.  Put water in the tray and the humidity will help the plant.  Another good way is to group your NIP with other plants. All plants release water through thier foliage's pores (called stomata), so having your NIP in a group will also help its need for 40-50% humidity.  It likes bright light, as well, and prefers to be turned every few days to give the tree even light.

NIP's do not need much in the way of feeding. Fertilize older plants every three to four months, and repotted or newly purchased plants every four to six months. Norfolk Island pines need only be repotted every three to four years.  Oh, and take the marbles out of the bottom of the pot.  Recent studies have found that when root plunge through the soil and reach such a drastically different medium, they stop growing or die.  Just water your NIP when the top 2 inches of soil is dry, and water them thoroughly. You can set the pot in the sink and water it until the water flows out through the bottom drainage holes.  Then, let the pot sit and drain at least another 15 minutes.

One last tip: When you do feed your NIP, try this recipe for fertilizer.  It's organic, promotes strong, healthy growth and helps prevent disease.:

1 Tbl. liquid or dry kelp/seaweed (save money by going to a health food store and buying powdered kelp. It's very inexpensive. Just mix it with water until it's the consistency of thin buttermilk.), 1 tsp. Blackstrap molasses, 1 Tbl.willow tea, 1 gallon of water. (The willow tea is made by taking a twig of willow - any kind - and cut it into 1 inch bits.  Soak it in boiling water for a couple of hours or at least until it cools completely. Strain out the twigs.) Put the fertilizer into a spray bottle and spray the plant's leaves, both top and undersides. You can then water in your NIP with this mix, as well.  The kelp has high amounts of nutrients, natural plant growth hormones, trace minerals and has been found to make plants more pest and disease resistant. Willow contains natural plant growth stimulating hormones. The molasses contains iron, sulfur and simple sugars which nourish the plant.

I hope I've answered your questions, and feel free to write anytime with any other plant queries you have!
Best of luck with your Norfolk Island Pine!
Eirinn

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

QUESTION: Thanks so much!  How would you make the potting soil?  I've read other articles, but they include ingredients to retain moisture.  I only have two potted plants.

Thanks!

Answer
Hi Emily! To make a good, all purpose soil, I mix equal parts humus/compost, coarse sand, perlite. To that I add 1/2 part composted manure.  All of these are available at garden centers, and, at least here in southern Illinois, the lot of it costs less than $10.  Some of the brand name potting mixes, such as Miracle-Gro and Sta-Green, for only 2 cubic feet, can cost almost as much or more depending on the garden centre.

For my Master Gardener students who want to make thier own potting soil, and get the benefit of knowing what they're putting thier plants into, but have very few plants, I get them to get a gardening buddy and split the potting soil ingredients in two.

Have a great gardening season!
Eirinn