Vivi's Orchid Corner

December 2000 - Volume 5, Issue 11

"Hapu Fiber"

Dear Orchid Friends:

I am always searching for the ideal medium in which to repot my orchids. I have experimented with many different potting mediums, blends and home made concoctions. I had luck with some and others.. well, that's why I am still searching.

A year or so ago, I purchased a bag of Hapu Fiber from Niu Nursery, LTD, a grower in Honolulu, Hawaii. I was disenchanted with the quality of the fir bark I was previously using, and decide to give this medium a try. Hapu Fiber comes from Chamissoi Live Fern Fiber. It is a twiggy, fibrous medium of dark brown color. It is considered a medium grade coarseness. I was not familiar with this medium and really did not know what to expect. Onward!…I was willing to experiment.

To use, soak the Hapu fiber in water and let sit to become saturated. Hapu fiber retains its shape and consistency when wet and becomes more pliable. I repotted oncidiums, phalaenopsis, cattleyas. I also repotted a few dendrobium species (group 3) such as Den. densiflorum, farmeri. I chose these particular plants because they needed repotting and were not doing well in their current mixture of bark and alifor.

With trepidation, I began the task of repotting my orchids. While strategically holding the root ball of the plant in the pot with one hand, I used my other hand to pack the Hapu fiber around the roots. The Hapu fiber was packed tightly around the root balls. I made certain the orchid roots were wet and pliable as well. Hapu fiber certainly is much easier on plant roots and your hands than a lava rock mixture. A big plus!

It took several weeks initially to see any impact from my newly potted orchids. Root growth appeared stronger in all the plants.. Wonderful! They needed a boost. The plants appeared a more vibrant green color and seemed to respond remarkably well to the new medium.

Now it is well over a year later and you wonder how the orchids faired. My cattleyas adjusted well and appear more robust and seem to flower more. There is a healthy proliferation of new roots which were quite lacking previously. The oncidiums produced wonderful healthy plants, but in the last few months, the plants grew higher up out of the pot. Roots are abundant, yet over time, perhaps the finer roots of the oncidiums found the material too dense. The oncidium plants themselves are strong and flower more, despite their habit of growing up out of the pots. One epidendrum, Epi. Joseph Lii, did not adjust to the Hapu fiber. Time to find another medium for this orchid.

My phalaenopsis (Phal. amabilis and Phal. violacea types) enjoyed an enormous surge of growth initially. After 8-10 months, the roots on these phals tended to grow out over the pot more frequently and the leaves began turning yellow. I added a small amount of bark with the Hapu fiber for the phals and they have made a comeback. These are in very small pots. I cannot truly make the correlation that the yellowing of the leaves were caused by the Hapu fiber. The discoloration in the leaves on the phalaenopsis may have been from other variables as well: change in watering schedule, fertilizer. I repotted the Den. Farmeri in a hanging wooden slat basket with the Hapu fiber surrounding the roots. The Den. Farmeri adjusted nicely, but again watch the amount of fertilizer used.

Here are a few observations about Hapu fiber. The fiber may have a tendency to retain a buildup of fertilizer salts, so water well in between fertilization. I cut back on my fertilizer mixture and the fertilizer schedule for these orchids. This made a difference. I may have been over fertilizing my plants which caused the fertilizer burn. Remember, experience comes with trial and error. The Hapu fiber does not appear to decompose as quickly as bark. This is a bonus to reduce the amount of time spent on repotting each year. The Hapu fiber drains well and does not retain too much moisture. After a year in the same medium, the Hapu fiber does capture a bit more water than when initially used, however , it stands up well with minimal breakdown.

I had minimal experience with Hapu fiber previously and did not know how my plants would react to it. I have learned more about its properties and how certain plants react to it. Would I continue to use the Hapu fiber? YES!.. but for certain orchids. The catts love it! Already I am thinking of how I can incorporate Hapu fiber with other mediums for use on my other orchids. I will adjust mixtures, watering schedules much better now having some actual hands on experience with it. I really like working with this medium.

OK...thumbs up for Hapu fiber. Do observe your plants and adjust accordingly.

Vivi