Re Jim Shields' outline of Len Doran's irrigation formula for Hippeastrums. I confirm completely Len's recommendations. Nitrogen as Ammonium [NH4] encourages root rot fungi, especially in high organic potting media. Calcium nitrate is Len's recommended ingredient. Bulbous plants, and particularly Hippeastrums, love calcium in generous measure. When I was breeding Hippeastrums [Amaryllis at that time because of Hamilton Traub and William Tjaden] I used an irrigation solution developed by Len that he had worked out to the degree that the particle size of the medium was critical for optimum benefit. I used it with my regular potting mix and it was utter magic. You could watch them grow! I've presented this formula several times at members' requests in the past 4 or 5 years. Would those members care to give a report on its efficacy? Warren Glover Sydney ----- Original Message ----- From: "J.E. Shields" <jshields@indy.net> To: "Pacific Bulb Society" <pbs@lists.ibiblio.org> Sent: Friday, November 10, 2006 11:18 AM Subject: Re: [pbs] Bulb Mix Curses > Linda, > Eventually you are going to have to feed those bulbs. However, something > with a balance like 6-12-12 is the wrong fertilizer mix. > > Bulbs use lots of nitrogen (N) and lots of potassium (K), but only a > little > phosphate (P). I suggest you use something like N-P-K 15-5-15 or > 20-10-20. > > Len Doran was an agricultural engineer for years whose hobby was > collecting > wild Hippeastrum all over South America. He worked out many years ago > that > Hippeastrum species need a lean potting mix (which is what Alberto has > described) and feeding with high N (as nitrate), very low P, and high > potassium (K). Len recommended using a very dilute liquid feeding every > time the bulbs were watered. > > You can use the same methods with Haemanthus and many other bulbs from > arid > climates as well. > > Dutch hybrid "amaryllis" (Hippeastrum) may well be a different story. In > South Africa, Hadeco Pty. grow them out in open fields in what looks to be > a sandy loam soil and with plenty of irrigation. They did not tell me > their fertilizer program! > > Best regards, > Jim Shields > in central Indiana (USA) where today has been beautiful Indian Summer > > > At 02:44 PM 11/9/2006 -0700, you wrote: >>............. >>I wonder if I should be fertilizing them? Would a tomato fertilizer work, >>like a 6-12-12? Would one application worked into the mix when I repot >>them >>suffice? >> >>Linda Foulis > > ************************************************* > Jim Shields USDA Zone 5 Shields Gardens, Ltd. > P.O. Box 92 WWW: http://www.shieldsgardens.com/ > Westfield, Indiana 46074, USA > Tel. ++1-317-867-3344 or toll-free 1-866-449-3344 in USA > > > _______________________________________________ > pbs mailing list > pbs@lists.ibiblio.org > http://www.pacificbulbsociety.org/list.php