Sylvain in Montreal, QC., asks:
I planted cuttings of my variegated pothos that had been rooted in water. That was over a year ago and they have not grown a centimetre. They live in the same conditions as their parent plants. I feed them with Acadie Seaweed (0.3-0.3-4) that works well for all my houseplants. I’m puzzled.
Judith Adam, horticultural consultant for Garden Making, says:
Yes, you should have some new growth by now. The fertilizer you’re using is higher in potassium (the third number), and that element isn’t the most useful for encouraging new roots and shoots. It might help to temporarily switch to a fertilizer with more nitrogen and phosphorous (the first and second numbers in the nutrient analysis), such as 9-14-8. That is considerably higher than your usual fertilizer, but one or two feedings might stimulate the pathos to begin growth, and then you could switch back to the usual fertilizer with lower numbers.
when roots are grown in water, it takes awhile for them to adapt to the new soil environment. The most important thing is to secure the roots. Initially, keep the plant a little moister than you would a regular plant; the water roots still need lots of water to keep existing foliage. Slowly start drying it down, encouraging new root growth. Be sure they are in a small planter as it’s easier to control water/dry down. Be sure to water the plant when it has dried down no more than 40-50% initially. Using the fertilizer as recommended above is a good idea. Remember most fertilizer’s instructions are based on the USA….in Canada, being north of 49, we get less light overall, so use 50% less than instructions read. ALWAYS best to fertilize less, a little more often. We fertilize every second week during active growth. ALWAYS be sure to fertilize only when the planting medium is moist. If you fertilize a dry plant you run the risk of burning those tender root hairs.