Gardening Indoors and Under Glass Part 2

[Ill.u.s.tration: A new scheme of sub-irrigation for flats. Some porous material such as sphagnum moss or excelsior (as here) is put on the open bottom and the flat watered by allowing it to stand in a sink or tub for a few minutes]

[Ill.u.s.tration: Cuttings ready for sand; the leaves have been clipped back. From left to right, heliotrope, geranium, "patience plant"]

[Ill.u.s.tration: Geranium cuttings ready to pot. Notice the roots, which should not be allowed to grow more than half or three-quarters of an inch long before potting]

CHAPTER V

STARTING PLANTS FROM CUTTINGS

While many plants are best started from seed, as described in the preceding chapter, there are many which cannot be so reproduced; especially named varieties which will not come true from seeds, but revert to older and inferior types.

Also it very frequently happens that one has a choice plant of some sort of which the seed is not to be obtained, and in this case also it becomes necessary to reproduce the plant in some other way.

Where large numbers of plants are to be started, and they may be had from seed, that is usually the best way in which to work up a supply: but where only a few are wanted, as for house plants or use in a small garden, propagation by cuttings is the quickest and most satisfactory method. Practically all of the house plants, including most of those which can be started from seed, may be increased in this way.

The matter of first importance, when starting plants by this system, is to have strong, healthy cuttings of the right degree of hardiness. Take your cuttings only from plants that are in full vigor, and growing strongly. They should be taken from what is termed "new growth," that is the terminal portions of shoots, which have not yet become old and hard.

The proper condition of the wood may be determined by the following test: if the stem is bent between the fingers it should snap (like a green bean); if it bends and doubles without breaking it is either too old and will not readily root, or too soft and will be almost sure to wilt or rot.

The cutting should be from two to four inches long, according to the plant and variety to be propagated. It should be cut off slant-wise, as this will a.s.sist in its being pushed firmly down into the cutting box.

It may be cut either near, or between a joint or eye--with the exception of a few plants, noted later. The lower leaves should be taken off clean; those remaining, if large, shortened back, as shown in the ill.u.s.tration facing page 29. Then the plant will not be so likely to wilt.

If the cuttings cannot be put in the propagating medium immediately after being made; keep them in the shade, and if necessary sprinkle to prevent wilting. I once obtained a batch of chrysanthemum cuttings from a brother florist who said that they were so badly wilted that they could never be rooted. I immersed them all in water for several hours, which revived them, and had the satisfaction of rooting almost every one.

The medium most commonly used in which to root cuttings is clean, medium-coa.r.s.e sand, such as builders use. It must not be so fine as to pack tightly, nor so coa.r.s.e as to fit loosely about the cuttings, and admit air so freely as to dry them out.

Make a flat similar to that used for starting seeds, but four or five inches deep. Place in the bottom an inch or two of gravel or coal ashes, covered lightly with moss or a single thickness of old bag, and then fill nearly full of clean sand. Make this level, and give a thorough soaking. After drying out for an hour or so, it is ready for the cuttings.

Mark the box off in straight lines, two or three inches apart, and insert the cuttings as closely as possible without touching, and to a depth of about one-third or one-half their length. A small, pointed stick, or dibber, will be convenient in getting them in firmly. Wet them down to pack the sand closely around them.

The best temperature for the room in which the cutting box is to be kept will be from fifty to fifty-five degrees at night. Like the seed box, however, it will be greatly helped by ten or fifteen degrees of bottom heat in addition. For method of giving this extra bottom heat, see page 26.

If the box is kept in a bright sunny place, shade the cuttings with a piece of newspaper during the heat of the day, to prevent wilting, and if the weather is so hot that the room is warmer than seventy degrees, an occasional light sprinkling will help to keep them fresh.

Never let the sand dry out or all your work will be lost. As a rule, it will require a thorough soaking every morning.

With these precautions taken, the cuttings should begin to throw out roots in from eight to twenty days, according to conditions and varieties. Do not let them stay in the sand after the roots form; it is much better to pot them off at once, before the roots get more than half an inch long. If some of the cuttings have not rooted but show a granulated condition where they were cut, they will be safe to pot off, as they will, as a rule, root in the soil.

The above method is the one usually employed. There is another, however, just as easy and more certain in results, especially where bottom heat cannot easily be had. It is called the "saucer" system of propagation.

Make the cuttings as described above. Put the sand in a deep, water-tight dish, such as a glazed earthenware dish or a deep soup plate, and pack the cuttings in as thickly as necessary. Wet the sand to the consistency of mud and keep the dish in a warm light place. The temperature may be higher than when using the sand box, and there will not be a necessity for shading. _The sand must be kept constantly saturated_: that is the whole secret of success with this method of rooting cuttings. Pot them off as soon as the roots begin to grow.

Cuttings made by the two systems described above are usually taken in autumn, or in spring. When it is necessary to get new plants during June, July or August, a method called "layering in the air" will have to be resorted to if you would be certain of results. Instead of taking the cutting clean off, cut it nearly through; the smallest shred of wood and bark will keep it from wilting, but it should be kept upright, for if it hangs down the end of the shoot will immediately begin to turn up, making a U-shaped cutting. The cuttings are left thus partly attached for about eight days or until they are thoroughly calloused, when they are taken off and potted, like rooted cuttings, but giving a little more sand in the soil and not quite so much water. They are, of course, shaded for several days.

Some of the plants ordinarily grown in the house, such as Rex begonias, rubber plants, sword ferns, are best increased by leaf cuttings, topping, layering or other methods differing from seed sowing or rooting cuttings. These several operations will be described in treating of the plants for which they are used.

Having carried our little plants safely through the first stage of their growth, it is necessary that we use some care in getting them established as individuals, and give them the best possible preparation for successful service in their not unimportant world.

CHAPTER VI

TRANSPLANTING, POTTING AND REPOTTING

Directions have already been given for preparing the best soil for house plants. This soil, sifted through a coa.r.s.e screen--say a one-half inch mesh--is just right for "p.r.i.c.king off" or transplanting the little seedlings.

Use flats similar to those prepared for the seeds, but an inch deeper.

In the bottom put an inch of the rough material screened from sods and manure. Give this a thorough watering; cover with an inch of the sifted soil, and wet this down also. Then fill the box nearly level full of the sifted soil, which should be neither dry nor moist enough to be sticky.

Take care also that this soil is not much--if any--colder than the temperature in which the seedlings have been kept.

It is usually best to transplant the seedlings just as soon as they are large enough to be handled, which is as soon as the second true leaf appears. Nothing is gained by leaving them in the seed boxes longer, as they soon begin to crowd and get lanky and are more likely to be attacked by the damping off fungus than they are after being transferred.

Find a table or bench of the right height upon which to work comfortably. With a flat stick, or with a transplanting fork (which can be had for fifteen cents) lift a bunch of the little plants out, dirt and all, clear to the bottom of the box. Hold this clump in one hand and with the other gently tear away the seedlings, one at a time, discarding all crooked or weak ones. Never attempt to pull the seedlings from the soil in the flat, as the little rootlets are very easily broken off.

They should come away almost intact, as shown facing page 48. Water the seed flats the day previous to transplanting, so that the soil will be in just the right condition, neither wet enough to make the roots sticky, nor so dry as to crumble away.

Take the little seedling by the stem between the thumb and forefinger, and with a small round pointed stick or dibber, or with the forefinger of the other hand, make a hole deep enough to receive the roots and about half the length--more if the seedlings are lanky--of the stem. As the little plant is dropped into place, the tips of both thumbs and forefingers, by one quick, firm movement, compress the earth firmly both down on the roots and against the stem so that the plant sticks upright and may not readily be pulled out. Of course there is a knack about it which cannot be put into words--I could have p.r.i.c.ked off a hundred seedlings in the time I am spending in trying to describe the operation--but a little practice will make one reasonably efficient at it.

When the flat is completed, jar it slightly to level the surface and give a watering, being careful, however, to bend down the plants as little as possible. Set the plants on a level surface, and if the sun is bright, shade with newspapers during the middle of the day for two or three days.

From now on until ready for potting, keep at the required temperature, as near as possible, and water thoroughly on bright mornings when necessary, but only when the drying of the surface shows that the soil needs it. Above all, give all the air possible, while maintaining the necessary heat. The quality of the mature plants will depend more upon this precaution than upon anything else in the way of care.

The little seedlings are sometimes put from the seed flat directly into small pots. I strongly advise the method described above. The flats save room and care, and the plants do much better for a few weeks than they will in pots. Where room is scarce, it is well to transplant cuttings into flats instead of potting them off. As soon, however, as either the transplanted plants or cuttings begin to crowd in the flats, they must be put into pots. How soon this will be depends largely, of course, upon the amount of room they have been given. As many as a hundred are often set in a flat 13x19 inches, but it is well to give them twice as much s.p.a.ce as that if room permits.

POTTING

Cuttings and small plants are put into two-inch or "thumb" pots. Some of the larger growing geraniums or very st.u.r.dy plants require two-and-one-half inch pots, but the smaller size should be used when possible.

The soil for pots up to three inches should be screened, but not made too fine. A coal-ash sifter, or half-inch screen will do. The soil should be made up as directed in Chapter III.

The pots should be thoroughly cleaned with sand and water, or by a several days' soaking, and then wiping out with a cloth, if they have been used before. An old pot, with dirt sticking to the inside and the pores all clogged up, will not do good work. Old or new, they should be immersed in water until through bubbling just before using; otherwise they will absorb too much moisture from the soil.

The method of potting should depend somewhat upon the condition of the roots of the cutting. If they are less than half an inch long, as they should be, fill the pot level full of soil, make a hole with the forefinger of one hand; insert the cutting to about half its depth with the other, rap the bottom of the pot smartly against the bench to settle the earth, and then press it down firmly with the thumbs, leveling it as the pot is placed to one side in an empty flat. (The jarring down of the soil should precede the firming with the thumbs, as this will compact the soil more evenly within the pot.) This should leave the soil a little below the rim of the pot, making a s.p.a.ce to hold water when watering; and the cutting should be so firmly embedded that it cannot be moved without breaking the soil.

With cuttings whose roots have been allowed to grow an inch or more in length, and plants with a considerable ball of roots--as they should have when coming from the transplanting flats--it is better partly to fill the pot. Hold the plant or cutting in position with the left hand and press the soil in about it with the right hand--firming it as directed in the former case. With a little practice either operation can be performed very rapidly. Florists do four to five hundred pots an hour.

When for any reason it is necessary to put a small or weakly rooted plant or cutting, or a cutting that is just on the point of sending forth roots, in a pot that seems too large, _put it near the edge of the pot_, instead of in the middle. This will often save a plant which would otherwise be lost, and at the next s.h.i.+ft it can, of course, be put in the center of the pot.

If no small pots are at hand, several small plants or cuttings can be put around the edge of a four-or five-inch pot, with good results. Care must be taken, however, not to give too much water.

As soon as the little plants or cuttings are potted up, give them a thorough watering and place them where the holes in the bottoms of the pots will not be clogged with soil. A large flat, in the bottom of which an inch of pebbles, coa.r.s.e sand or sifted cinders has been put, will be a good place for them. Keep shaded during the hot part of the day for three or four days. At first the pots may be placed as close together as possible, but in a very short time--two weeks at the most, if the growing conditions are right--they will need to be put farther apart.

Nothing will injure them so quickly as being left crowded together where they cannot get enough air. Better, if necessary, give or throw away half of them than to attempt to grow fifty plants where you have room for only two dozen.

As before, water only when necessary, _i.e._, when the surface of the soil begins to look whitish and dry. Then water thoroughly. Until by practice you know just what they need, knock a few out of the pots, say fifteen minutes after watering, and see if the ball of earth has been wet through to the bottom; if not, you are not doing the job thoroughly.