Growing Kalmias and Rhododendrons from Seed 



By Wm. Anderson 2S£ 



[Editor's Note : The writer in his capacity as superintendent on the estate of Mr. Bayard 

 Thayer, at South Lancaster, Mass., has been most successful in doing what he here describes. 

 Most of the plants offered in the trade are native collected material, and while to a certain 

 extent its gathering may be justified, it were surely far better to use seedling nursery stock 

 which is not only more safe in transplanting but increases the stock of our most beautiful 

 native shrubs, an object which should be dear to our hearts.] 



MOUNTAIN laurel (Kalmia) and 

 rhododendron, native hardy, 

 evergreen shrubs are so fully 

 appreciated as garden plants 

 that our countrysides are being denuded. 

 That might be all well enough, but for the 

 fact that an enormous percentage of such 

 collected plants die. On the other side 

 is the comparative ease of raising plants 

 from seed with the certainty of getting 

 better plants in the long run. This is 

 especially true of the kalmia. This can 

 best be collected when four or five years old, 

 (or when from one to two feet in height). 

 Transplanting affects their growth and they 

 show it for several years. On the other 

 hand, I have found that in four years from 

 the time of sowing the seed, Kalmia plants 

 such as shown in the adjoining illustration 

 can be obtained. These stand the trans- 

 planting with practically no loss of growth 

 or strength. 



Many people who have tried raising 

 kalmia from seed and have been unsuccess- 

 ful believe that it is cheaper in the end 

 to buy the plants from a dealer. I have 

 raised from seed about 300,000 plants and 

 careful records show that it has been cheaper 

 and better than to have bought them. 



Seeds from plants having pink or nearly 

 red flowers produce plants which are more 



Rhododendron plants 18 months old — These are 

 seedlings of new species collected in China by E. 

 H. Wilson 



vigorous and rapid-growing than 

 seed from the lighter colored 

 or nearly white varieties. 

 From the many thousands of 

 seedlings that I am now raising 

 many decided breaks or variations 

 in color of flowers, and perhaps in the 

 habit of the plants, are expected to take 

 place. For this reason seed has been taken 

 from the nearly white, and from red vari- 

 eties with the hope that a pure white or pure 

 red variety may be obtained. Larger flow- 

 ers are also hoped for. 



As far as possible the conditions under 

 which these plants thrive in their wild state 

 ought to be imitated while they are in the 

 greenhouse or nursery. 



November is the best time to collect the 

 seed; it is not ripe until that time and if 

 gathered earlier cannot be so easily cleaned. 

 If greenhouse accommodation with artificial 

 heat is available, February or March is 

 the best time to sow the seed. For this 

 purpose a mixture of four parts leaf soil, 

 two parts chopped sphagnum moss and one 

 part sand, well mixed together and rubbed 

 through a fine sieve is most suitable. 



Select clean 6-inch or 8-inch pans one- 

 third filled with crocks or rough material 

 to give perfect drainage. Then fill up 

 with the soil mixture and tamp it moder- 

 ately firm. Give the pans one good water- 

 ing and sow the seed, not too thickly, and 

 do not cover with soil. Place the pans 

 on a well-shaded bench in a temperature of 

 from 55 to 60 degrees. If the seeds are 

 sown in February or March, and the green- 

 house has been kept moist and well shaded, 

 very little watering will be needed until 

 the seeds germinate, which should be in 

 three or four weeks after they have been 

 sown. If they do get dry, water carefully 

 and thoroughly and then do not water 

 again until they are dry. That is a very 

 important point to keep in mind. The 

 majority of those who have been unsuccess- 

 ful in trying to raise kalmia from seed may 

 trace their failures to overwatering. 



Seed can also be sown on pure sphagnum 

 moss; it germinates freely then and grows 

 well up to a certain point, but the seedlings 

 cannot be so early or safely transplanted 

 as when grown in the soil. 



When the little seedlings have made 

 three or four small leaves, they can be safely 

 handled for the first time. They will reach 

 this stage of growth in about three months 

 from the time the seed has been sown. 

 Transplant from the pans into flats, in 



43 



Home grown mountain laurel plant (Kalmia) 

 three and a half years from sowing seed. Note the 

 strong fibrous root system 



which drainage material has first been 

 placed, using a mixture of eight parts leaf 

 soil, three parts loam and two parts sand, 

 thoroughly mixed and passed through a 

 half-inch screen, and pressed moderately 

 firm into the flats, but not hard. 



For kalmias, the black material known as 

 peat had better be avoided. Rhododen- 

 drons and azaleas may do fairly well in it 

 but kalmias do not like it. For the first 

 summer the seedlings do better if kept in 

 the greenhouse, where watering and shading 

 can best be attended to. If greenhouse 

 space cannot be given transfer them to a 

 frame and shade with lath shades. If there 

 is any indication of damping among the 

 seedlings during the early stages of growth,, 

 increase the ventilation and sprinkle the 

 affected parts with hot sand which will not 

 affect the seedlings but simply check the 

 damping. 



If coldframes are depended upon instead 

 of the heated greenhouse, sow the seed 

 about May 15th, and let the plants grow 

 on in the seed pans for the first season, 



