NOTES ON BULB 
FORCING HYACINTHS 
When Hyacinth bulbs are received they should be unpacked 
immediately. The bulbs should be carefully spread out on trays. 
Keep them as dry as possible and in a well-ventilated room 
between 55 and 60° until potted. 
Potting for early forcing should be done as soon as possible 
after the bulbs are received. For later forcing, bulbs should be 
potted about 3 months before forcing. Use a light, porous soil 
mixture—sterilized soil is best. If planted in beds, cover the 
bulbs with 4 to 6 inches of soil. Immediately after potting, 
place in a bulb cellar or bury out-doors in a shaded location 
under 6 inches of sandy soil covered with a straw mulch so they 
won't freeze. During this storage period, Hyacinths make their 
root system which is necessary before forcing starts. Ideal tem- 
perature for storage after planting is around 50°. They should 
be watered regularly. 
As soon as the root system is well established and the growth 
is well above the pots, they can be moved into a 65 to 75° 
location for forcing. Until foliage is well out and buds are 
showing, the plants should be kept in a fairly dark place. 
During the last 10 days or 2 weeks the plants should be moved 
out into the light and a cooler temperature for proper coloring 
of the flowers. Thruout this forcing period, Hyacinths should 
be kept warm and moist with frequent waterings. 
Approximately a month of forcing is required to bring Hy- 
acinths into flower during December, January, February and 
March. 3 weeks will suffice for Easter. 
Prepared Hyacinths have been treated with heat either in the 
fields when the bulbs are produced or immediately after digging 
so that the flower bud emerges quicker than normal. Prepared 
Hyacinths are forced exactly the same as outlined above except 
that they can be brought out for forcing sooner—by December 
Ist or earlier. 
Top size bulbs should be used for forcing. 
FORCING TULIPS 
Tulip bulbs for forcing should be planted in benches, flats 
or pots as soon as possible after receiving them. If not pos- 
sible to plant immediately, they should be taken out of con- 
tainers and spread out in a cool (48° is ideal) dry location. 
Bulbs give off heat and are apt to “heat” if allowed to remain 
in bags. Bulbs should be grown at 48° from planting time. 
Plant in a loose, well drained soil, preferably sterilized. Water 
regularly so the soil is never allowed to become dry. 
As soon as the shoots emerge from the ground occasionally 
spray with a Fermate solution of | lb. to 100 gal. of water. 
This will control fungous diseases that may destroy foliage. 
Free ventilation and care not to wet foliage also helps prevent 
the spread of diseases. 
Varieties vary in the time required for forcing. The follow- 
ing table shows the principal varieties used and the dates to 
begin forcing and the date of expected flowering. Forcing con- 
sists of raising the temperature to 55° for 2 weeks and then 
increasing to 60°. Forcing temperatures should not be allowed 
to go much above 60° any time. These temperatures should 
be maintained uniformly day and night. 
Pre-cooled bulbs have been specially treated by storage at 
about 48° so that the stem and flower buds elongate within 
the bulb. With this treatment earlier flowering is possible. 
PRE-COOLED BULBS REGULAR BULBS 
Begin Flowering Begin Flowering 
Variety Forcing Date Forcing Date 
Albino Dec. 5 Jan. 5 Dec. 14 ‘telapoAl 
Golden Harvest Dec. 15 A Yolq ral he! Dec. 2] Feb. | 
Red Pitt Dec. 20 Jonugiz 0 Jarra Feb. 10 
Rose Copeland Dec. 10 Jan. 10 Dec. 21 Feb. | 
Wm. Copeland Dec. 10 Jan. 10 Dec. 21 Feb. | 
Wm. Pitt Dec. 20 Jan. 20 Dec. 31 Feb. 10 
Utopia Dec. 27 Jan. 27 Jan. 7 Feb. 17 
Bartigon Dec. 26 Feb. 5 Sian 15) Feb. 20 
WEST CHICAGO 
ILLINOIS 
CULTURE—Continued 
Most Cottage or Darwin varieties are suitable for forcing. 
The Single Early and Mendel varieties flower earlier but don’t 
produce as good quality flowers. 
Best results are obtained by using large sized bulbs. 
FORCING DAFFODILS 
Bulbs should be unpacked and planted as soon as received; 
planting should be as close together as possible—‘’bulb on 
bulb.’” Particularly pre-cooled bulbs will be delayed consider- 
ably in flowering by allowing the bulbs to remain in their cases 
for even a few days. Daffodils prefer a loose, well drained soil, 
preferably sterilized. Bulbs should be grown at 48° (either in 
a bulb cellar, out-doors or in greenhouse bench) until the shoot 
is at least 3 inches long—longer for later forcing does no harm. 
Forcing consists of raising the temperature to 60° for 3 weeks 
and then to 65°. This temperature should be maintained uni- 
formly day and night. 
American-grown Daffodil bulbs are best for mid-winter forc- 
ing. For earliest forcing, pre-cooled bulbs are recommended. 
Dutch bulbs may be used for late winter and spring flowering. 
King Alfred, American grown Double Nose No. 1, pre-cooled, 
is the generally accepted extra early forcing variety. These 
bulbs can usually be forced beginning the end of November. 
If not pre-cooled, forcing usually can be started about Dec. 15. 
FORCING WEDGEWOOD IRIS 
WEDGEWOOD: American stock and the largest bulb possible 
should be used for pre-cooling and early forcing. The smaller 
size bulbs should be used for later flowering in both pre-cooled 
and regular. The sizes available today are: 8'%2/9, 9/10, 
10/11 and very few 11/up. 
PRE-COOLING: Bulbs must be pre-cooled a minimum of 5 
weeks in a constant temperature of 50° with a relative humid- 
ity of 70% or more. Bulbs should be turned or moved each 
week so that the cool air will reach all bulbs in the bag or in 
the case. They should be planted immediately as taken from 
cold storage in as cool a soil as possible and grown for 10 days 
to 2 weeks in a temperature between 50 and 55°. Gradually 
increase the temperature to 60° for best results. 
PLANTING: Iris can be planted in pots, flats or benched direct. 
Have a minimum of 4 to 5” of soil so there is ample room for 
development of the root system. Spacing can be approximately 
2x4 or 3x4 for early planting. The later the planting the 
closer they are spaced. The early planted stock will have very 
heavy and strong foliage that will require more room to pre- 
vent them from going blind. The preferred method of plant- 
ing is to thoroughly soak the bench and push the bulbs into 
the soil, putting on a covering of soil or peat approximately 1/2 
or ]‘’—then re-water again so the bench is thoroughly wet. 
Iris roots will not develop satisfactorily if the soil is allowed 
to dry out during the first few weeks. 
WATERING: Do not allow your Iris bulbs to dry out from the 
time they are planted until the crop has been harvested. The 
temperature of the water used should be as near the air tem- 
perature in which you are growing your Iris, as possible. It is 
a severe shock to the crop if grown in approximately 60° to 
water with temperatures of 50° or less. The temperature of 
the water has caused a great deal of difficulty in early forcing. 
CUTTING IRIS: Usually Iris are pulled—pulling the bulbs out 
of the soil or the maximum stem length from the bulb. They 
should be put in water immediately if going to the market the 
following day. If you wish to hold them a few days, put in a 
refrigerator in a temperature of 45 to 48° without water. At 
the time you wish to use them bring them out and put them in 
water the night before and they will open up very nicely for 
you. Most growers prefer to cut Iris when 34 of an inch of 
color is showing on the bud. 
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