It is with great pleasure to read Nick's letter on this subject. I agree fully with his findings. I have never grown nerines (of any species) in clay pots) but I have grown other bulbs and cacti in them. That ended about two years ago after I saw the roots all circling the clay surface, thereby limiting their search for moisture and nutrients to a small fraction of the potting mix volume . What finally decided me to dump clay pots was the difficulty in repotting. So, one final act of clay unpotting was followed by piling up the old clay pots. With cacti, the nature of their roots makes them inextricable from the porous clay surface without serious root damage during extrication. Their rootlets penetrate into the clay walls in search of water. Modifying the potting mix to have a slightly more open (aerated) character in plastic containers than in clay pots is all that I found necessary. I still have those piles of clay pots! Perhaps I'll find a use for them. Andrew San Diego -----Original Message----- From: pbs-bounces@lists.ibiblio.org [mailto:pbs-bounces@lists.ibiblio.org] On Behalf Of Nick de Rothschild (by way of Mary Sue Ittner<msittner@mcn.org>) Sent: Monday, October 03, 2011 11:53 AM To: pbs@lists.ibiblio.org Subject: [pbs] Growing nerines Hope this finds its way onto the forum: For those of you that grow nerine sarniensis here is an observation- (and we knows what we are talking about!) We frequently make a comparison between bulbs grown in clay pots and bulbs grown in plastic pots and can now make a definitive statement: The bulbs in clay pots shrink by to 30% of their pre-flowering size whilst the bulbs grown in plastic pots continue to hold their full pre-flowering size - you know how the bulb swells in August-September (and if your bulbs don't swell in September then you are doing something wrong (if you are in the Northern Hemisphere of course). We also note that seedling bulbs can be kept in stasis in small plastic seed trays for many years without adverse effect, other than the bulb size stays small, and only when repotted (we have some bulbs in this growing scenario that are 8 years old) do the bulbs then get up to a decent size and the tiny bulbs, like bonsais, produce diminutive flower heads- we had a collection of the Zinkowski nerines that were tiny bulbs to start with and they had tiny flowers, and I thought that they were poor, however given the Exbury Regime, they are now reaching their full potential as they should be. Of course, you might say, that other factors are involved... so I can also say that the ones in clay and the others in the sample that I measured against were potted up in the same year. We also split the pots and examine the roots and notice substantial differences in root growth patterns between clay and plastic. In clay the bulbs put a out much greater mass of fibrous roots that cling to the clay surface, whereas in plastic they are more evenly spread and not in such abundance. We surmise, therefore, that the bulb is losing mass to this root growth, which is deleterious to flowering. With our potting mix of 5 parts John Innes No 3, 1 part course grit, 1 part sand, 1 part bulb fibre, 1 part rotten manure, we are achieving 95% flowering in all our 2 litre show pots. We feed with a 20-20-20 fertiliser in a weak dilution from now until March. This year the Exbury Nerine Collection (see <http://www.nerines.com/>http://www.nerines.com/ for varieties etc) has flowered about 3 weeks earlier than usual- This we attribute to a really dull August when the weather here in the southern UK was miserable (please don't feel sorry for me I went to Zanzibar instead) however it was noted that there was almost autumnal temperature fluctuations with very cool nights. This, we believe, triggered the flower spikes to start growing, and once this happens they do not stop even if the temperatures then rise again.. Now we have just had a heat wave with record 30 degrees at the start of Oct. and quite a few are wilting faster. We keep a 50% shade over them for most of the year. So my message to all you n. saniensis growers is- ditch your clay and go plastic.... Nick de Rothschild