FERTILIZERS—Continued 
applying the quicker acting chemical salts in the hope of obtain- 
ing quick growth. An exception to this rule is in regard to the 
use of sawdust as a soil amendment or mulch. In areas close to 
lumbering industry, it is cheaper than peat moss, serves the 
same purpose as a mulch, and is an excellent physical addition 
to either a heavy or light soil. In time it becomes a source of 
plant food, but the period of decompostion is a lengthy one 
unless quick acting nitrogenous fertilizers are added to speed up 
the bacterial action and hasten the decompostion of lignins and 
celluloses into humus. For every one hundred square feet of 
sawdust one inch thick, apply two pounds of Sulphate of Am- 
monia, either dry or in solution. 
Whatever method is used, it is good insurance to water the 
plants thoroughly after applying the fertilizer so that there is 
no likelihood of a burn. he sulphate of ammonia may be ap- 
plied in the spring and again in three applications at six week 
intervals. On older specimens which have been in place for some 
years, a top dressing of well decayed barnyard manure is bene- 
ficial if applied in fall as a mulch and allowed to be washed in 
by winter rains and snow. There are several brand name acid 
fertilizers on the market, usually with a cottonseed meal base 
which are slow acting and safe to use when the manufacturer’s 
directions are followed. 
The use of so called leaf feeding fertilizers containing urea and 
applied via the foliage is becoming more widespread among 
nurserymen and one or two proprietory mixtures now on the 
market have been used with success on Rhododendrons. 
It is customary to begin feeding just prior to flowering and 
then repeating the applications at month intervals until August 
when feeding is discontinued. 
WATER 
Rhododendrons imbibe water in quantity during the growing 
season, but overwatering can be disastrous if the soil has been 
insufficiently lightened and water accumulates around the root 
system. So again the importance of good drainage is emphasized. 
The value of a mulch is evident since a layer of loose humus 
absorbs many times its weight in water and releases it slowly 
into the atmosphere so that the humidity around the plant is 
increased. 
When Rhododendrons are purchased from the nursery, the 
root ball usually contains a high percentage of peat moss. This 
is especially true in the case of plants in smaller grades. Once 
peat moss is allowed to become dry, it takes some time for water 
to penetrate thoroughly into the root ball. To avoid possible 
injury to the plant due to dry roots, immerse each ball in a 
tub of water preparatory to planting and then water thoroughly 
after the plant is in place. On steep slopes or in the case of large 
specimens it is sometimes necessary to resort to sub-irrigation 
in order that the water might reach the entire root area, in 
which case the use of a water spike is recommended. This is an 
attachment which fits on the hose and is pushed into the root 
area and the water is forced into the ground through holes in 
the tubular attachment. The canvas hose type of sprinklers, 
called Soil Soakers, are excellent for watering and do a thor- 
ough job without eroding the soil or dissipating the moisture 
into the atmosphere. 
Most Rhododendrons are native to regions where the humidity 
is relatively high so that during the warm summer days, over- 
head sprinkling night and morning is appreciated, and assists 
materially in the reduction of insect populations. In our nurs- 
ery, the bulk of our plants from two years old and up are grown 
in full sun and during hot days, sometimes 99° to 100° with 
humidity down to 12, the overhead sprinkling system is turned 
on and allowed to run from noon until three or four in the after- 
noon. Burning of the foliage has not occurred when the sprin- 
klers are left on for a three or four hour period, However, 
there has been burning of the leaves when sprinklers were not 
turned on or when they were run for only a short period. Since 
the average garden is not equipped with overhead sprinklers, it 
would be wise to confine the sprinkling to early morning and 
late evening. Where lath shade is employed or where there are 
overhead sprinklers in operation, then by all means turn them 
on during the heat of the day. 
acai SHADE AND PROTECTION 
i RH ANGaWES PREVAILING In the Willamette Valley, 
si SED WINDS where our nursery is located, 
f ATL tT the Weather Bureau records 
tT RP RE DEEL ae SRy showed that we had over 4000 
Pere HL sunlight hours for last year. 
|] Tenoonaey Big an Serge am 
PROTECTION are not uncommon although 
AGAINST WIND 
the mean is 52.1°. Despite the 
fact that Rhododendrons are recommended as shade loving 
plants, the majority of our stock, after it has attained an age of 
three years, is grown in full light in open 
nursery beds. This 
is done to promote aa es 
sturdy growth and ae \ 
to assist in the 
formation of 
flower buds. 
Around the 
home or in the 
garden where the 
qualityeorerme 
bloom is of utmost 
importance, it is 
recommended that 
the plants receive 
a few hours res- 
pite from _ direct 
sunlight during 
the heat of the 
day. 
If the plants are being used as a foundation planting, then the 
north side or east side of the house is to be preferred unless 
there are trees on th south and west sides to protect them. The 
ideal location is where the plants receive the benefit of shade 
from high trees without being directly underneath the branches. 
It must be borne in mind that it is just as important to protect 
the plants from strong winds as it is to provide shade, and a 
belt of high shrubs or high fence to the windward side will pre- 
vent a great deal of damage to the foliage as well as the 
blossoms. Dense overhead shade is detrimental to their welfare 
and induces the plants to become drawn and leggy with a con- 
sequent reduction in vigor and flower buds. Where Rhododen- 
drons are planted in woodland, a periodic thinning out of over- 
head branches is necessary to admit sunlight. In a new garden 
where shade is insufficient or where the trees have not at- 
tained the size to throw much shade, then temporary lath shades 
will make a splendid substitute until the trees become more 
mature. When selecting a planting site, avoid hollows or slopes 
which lead into a hollow where cold air is likely to settle. Such 
a location can prove to be disastrous during winter and early 
spring. If possible, choose a long gentle slope where there is 
free escape for cold air as well as excess water. 
In climates known to be severe, Rhododendrons will need pro- 
FILL IN AROUND BRANCHES WITH — {ction during winter fo 
LOOSE STRAW OR FERN LEAVES ees 
temperatures, This may 
. : 
be accomplished by 
building a wooden frame 
structure covered with 
heavy burlap sacking. 
Within the frame the 
plant should be further 
insulated against cold by 
packing straw or fern 
Through the branches. 
MULCH ON TOP OF ROOTS Evergreen boughs, 
; pointed at the heavy end, 
and pushed into the ground around the base of the plant so that 
the branches cover the Rhododendrons make an excellent and 
quickly built cover. Pine or any of the cone bearing trees may 
be used for this purpose. 
PRUNING 
Gardeners are often confronted with the problem of a Pink 
Pearl or similar large hybrid which has overgrown its position 
in the garden. They have no al- 
ternative but to prune and it can 
be done without too much dam- 
age to the plant provided a little 
care is exercised. Rhododendron 
leaves occur in whorls at the 
end of each growth. In the axils 
of the leaves are growth buds 
which remain dormant unless 
they can be forced into growth 
by removing the stems beyond 
the point of their origin. By 
cutting back the stems to a 
whorl of leaves below, these POSITION~__ 
buds are induced to break so OF CUT PS 
that a plant might recover its - DORMANT 
growth the same spring. BUDS ¢ 
TEMPORARY 
SHADE 
Please read EXPLANATIONS on page 6 regarding HARDINESS and QUALITY RATINGS 
