SOILS AND FERTILIZERS 
Carnations grow well in a variety of soils, but fibrous loam soils which remain reasonably porous and 
permit free drainage of surplus water throughout the growing season are easiest to manage. Blue grass 
sod, to which rotted manure has been added plus an application of superphosphate, gives uniformly 
good results. Since the average carnation crop will be in the bench about a year, attention and time 
put on good soil preparation are both necessary and justifiable. 
STEAM STERILIZATION 
Carnations can be grown year after year in the same soil, if it is thoroughly steam sterilized annually 
and the organic matter replenished. Steaming is a dependable method of eliminating soil-borne carna- 
tion diseases, both from the soil and the bench boards, Some growers even sterilize new soils, calcu- 
lating that the disease-control insurance and the killing of weed seed justify the additional cost. 
Results on steam sterilized soil are comparable to those on good new soil, if all of the rules are followed. 
To avoid some possible pitfalls, the following practices are suggested: 
1. Reduce nutrient levels and soluble salt content of the soil prior to sterilization by keeping to a 
minimum the late feedings on the previous bench crop. Also the last one or two waterings 
of the preceding crop can be much heavier than usual to accomplish leaching prior to steri- 
lization. 
2. Add organic matter to the soil liberally before sterilizing — about one-fourth by volume of 
rotted manure, chopped legume hay or peatmoss. 
3. Steam sterilize the soil so that a minimum of 180° F. is reached and held for thirty minutes 
in every part of the bench soil. 
4. If time permits, leach heavily with water after sterilizing and let the bench stand for a week 
to ten days before planting. 
5. If time does not permit for the procedures outlined in Point No. 4, plant after the soil is cool 
and accomplish some leaching by going over the bench a half-dozen times with moderate 
waterings, immediately after benching. 
6. Apply 5 pounds of gypsum (calcium sulfate) and 5 pounds of superphosphate per 100 square 
feet of bench space, and mix into the soil well before planting. 
7. Do not use a complete fertilizer at benching time, but wait until after the plants are estab- 
lished and growing. 
8. After the original watering-in of newly benched plants, do not let the soil become hard and 
dry before giving the second and subsequent thorough waterings. 
OTHER STERILIZATION 
Chemical sterilization of carnation soils is receiving a good deal of attention, and some soil fumigants 
and chemicals are useful in the control of specific disease, insect and weed pests. For all-round effective- 
ness, steam sterilization still holds the No. 1 position. 
Hot water sterilization is used by growers to some extent, and in some areas is preferred to steaming, 
probably because the extremely large volume of hot water used to achieve sterilizing temperatures ac- 
complishes something in leaching not ordinarily achieved with the steam method. For thorough 
sterilization with hot water, the minimum temperature of 180° F., held for thirty minutes, must be 
satisfied. 
NEW SOIL 
When sterilizing is not practiced, new soil should be brought in for each successive crop of carna- 
tions. Avoid reusing soil that has grown carnations during the previous five years. A good sod soil is 
superior to field soils that have been in cultivation. Mix about one-fourth by volume of manure, peat 
or chopped legume hay with. the soil. Also incorporate 5 pounds of superphosphate per 100 square 
feet before planting. Complete fertilizers are better withheld at that time and applied after the plants 
are established, unless soil tests show decided deficiencies in nitrogen or potassium. The young plants 
generally start off more rapidly in a lean soil, and are then soon ready for feeding. 
