Raising Plants From Seeds
( Originally Published 1923 )
Many of the best house plants can be raised from seed in the ordinary living rooms, or where potted plants are grown in a window during winter. It is a question whether you actually save anything by raising your own plants; in all probability you could get them as cheaply and as good, if not better, from the florist, but there is no question about the fun in growing plants from the seed. There is a satisfaction in having things all your own, and the work offers engagement indoors at a time when gardening work outdoors is slack.
HOME MADE "FLATS"
'Where only a few plants are to be started, unglazed pots or seed-pans are often used, but "flats" are cheaper. To make these buy from a grocery store some soap boxes. A convenient size is twelve by fifteen inches. Cut them into three-inch sections and nail bottoms on these, taking care to leave cracks between the boards or make four or five one-inch holes for drainage. The sides may be painted, if they are to be used in the house. These flats are better than pots both for starting the seed and pricking off, as they save care in watering, room, time, and trouble and the mOisture in the soil is much more constant than in a small pot.
The flats being ready mix the soil. A good seed soil is made from equal parts (1) fibrous loam from the compost heap, (2) sand, and (3) leafmould, woods earth, or peat.
Over the holes or cracks in the flats put a one-half-inch layer of broken potsherds, coal clinkers, or gravel for drainage. Then put through a sieve part of the already mixed seed soil. You will then have two lots of soil, one coarse the other fine. Spread a one-half-inch layer of the coarse material over the drainage material that is already in the flat and on top of that fill the flat to within half an inch of the top with the fine, screened soil. Pack the soil in the corners and along the edges with your hands, because if you do not, it will settle there more than in the middle, and the waterings will wash down the soil, uncovering and often taking the seed with it. Firm the whole by means of a damp brick or board.
SOWING THE SEED
Make drills about two inches apart using a piece of narrow board as a marker, merely pressing it lightly into the soil for a quarter-inch or so. Sow the seeds thinly and evenly in the drills, and cover lightly; the best way to cover the seeds is to screen the soil on them, using a screen which has a mesh about the size of that in mosquito netting. A good rule to follow when covering seeds is to put on a layer of soil which is as deep as the diameter of the seeds. Sand, dry sphagnum, cocoanut fibre, or leafmould which has been rubbed through a fine screen, make very good coverings for seeds. They never get hard or bake, making an ideal covering — light, easily pushed through by the tender seed-shoots, and retentive of moisture.
Water the soil thoroughly after sowing. The best way is to set the flat in a large pan partly filled with water, allowing it to soak up from below. This is better than overhead watering because no matter how fine a spray is used it is liable to wash the soil. Another way is to water through a sheet of blotting paper. Place the blotting paper on top of the seed bed and slowly apply the water, allowing it to soak through the paper. The drip is thus avoided.
Cover the box with a loose-fitting pane of glass to keep a more humid atmosphere, thus reducing evaporation from the soil. Every day remove the glass and wipe off any water of condensation which may be on it. Place the flat in a position where it will receive all the light possible, but shade it from the direct sunlight.
THE DETAIL OF "PRICKING OUT"
Pricking out is the first transplanting of the seedlings, and needs to be done tenderly. As a rule as soon as the seedlings have made their first two real leaves it is time to "prick out" into other flats, prepared similarly to the seed flat.
Do not try to take each single seedling from the seedbed. Take out a portion of soil which has a number of seedlings in it, lay it on its side and gently separate the soil.
The dibble is a very useful tool for this purpose. It is made from a small piece of wood one-fourth or three-eighths of an inch square, or round, and about four inches long. Make a tapering point — two inches long — on one end; the other should be drawn down to an edge. This latter will be very useful in separating the plants and firming the soil about the seedling when it has been set in the new soil.
Put the little plants in rows an inch or two apart, water thoroughly, and shade for several days from hot sun with newspapers. Do not water again until the surface of the soil begins to dry. Do not delay the pricking off, do it just as soon as the little seedlings can be handled, for they may all be lost by "damping off," or they may become drawn. Should the seedlings begin to damp off apply some hot sand, sprinkling it on with a fine-meshed sieve.
As soon as the plants need still more room prick them out singly into thumb (two-inch) pots. When transplanting insert the plant-let a little deeper than it was in the old bed.
THE FATAL FROST
All the plants named later in this chapter can be grown in an Ordinary window, where ordinary living room conditions prevail. The temperature should be from 50 degrees to 55 degrees at night, and under no circumstances must the freezing point be reached. The day temperature, if you can control it, may be allowed to rise 10 degrees on dull days and 15 degrees or 20 degrees will do no harm when the sun shines.
RED BERRIES FOR CHRISTMAS
Nothing is easier for the owner of a sunny window than to grow a few plants of the Jerusalem cherry (Solanum Pseudo-Capsicum), as the spare room is needed only when the weather gets warm outside. I don't know of a more generally satisfactory Christmas plant either. It is symmetrical, full of bright red berries, and may easily be had with a head a foot in diameter for the holidays from seeds sown during winter or spring. The "cherries" hang on for three months but in a gas laden atmosphere the leaves soon drop off.
Sow the seeds in February, and as the plants fill their pots with roots, shift to a slightly larger pot.
During summer, plunge them in a partially shady place outdoors, and give plenty of water. By pinching back, and turning, the plants may be kept symmetrical. When taken into the house in the fall, see that they get plenty of air and plenty of water at the roots, and syringe the foliage. Be careful about watering while the fruit is setting and ripening. To carry the plants over from one year to the next, cut back the old plants in the spring, and give the same treatment as they had the previous summer.
A PLANT FOR BASKETS
The best decorative plant for shelves, baskets, or hanging baskets is the foliage asparagus (A. Sprengeri). Its foliage is much coarser than that of the fine-leaved asparagus (A. plumosus), somewhat resembling light, glossy-green pine-needles, stuck endwise upon viney stems. But its branches hang down gracefully on all sides, and make a handsome, symmetrical plant. If kept growing freely all summer the plant will produce an abundance of red berries about Christmas time, making a welcome addition at that season.
VINES THAT FLOWER ALL WINTER
I think no plants are more artistic, more beautiful for room decoration than the climbing vines. The fact that they are so seldom used for this purpose gives them an added distinction. For myself, I prefer the ivies, on account of their simple strength and grace; and they are best got at the florist's. But several good house vines are best raised from seed. The cup-and-saucer-flower (Coboea scandens), and Thunbergia alata, with its varieties, are the best two flowering vines for the house. The former has purple, bell-shaped flowers, two inches across, the latter having, according to the variety, blooms of golden yellow, rich orange, white and blue, or pure white, with white or dark centres, and about one and one-half inches across. Both these plants are perennials, but are often grown as annuals. They are easily raised from seed, are strong, rapid growers, and have very decorative foliage.
If seeds are sown early in the year — January or February — the plants can be used outdoors during the summer, and in September may be cut back, dug up, and potted for the window garden. By making successive sowings once a month until the end of May, the Thunbergia may be had in bloom all winter. The Coboea seeds must always be set edgewise in the ground.
Two other vines which will give lots of pleasure if you have a sunny window are nasturtiums and morning-glory. I have seen morning-glory make a growth of six or seven feet when grown in an ordinary cigar box. The flowers and foliage were not as large as they would have been if grown out-doors, still the plants were healthy and flowered freely, affording much pleasure to the grower.
The nasturtium will produce a wealth of red and yellow flowers, but it absolutely demands an abundance of sunlight; if you cannot grow it in a south window where it will receive direct rays from the sun for the greater part of the day, flowers need not be expected. Seeds sown in July or August in two-inch pots, from which they are shifted to four-inch, and later to six-inch pots, will flower some time about Thanksgiving or Christmas, and will continue flowering the rest of the winter. A six-inch pot is sufficiently large for one plant, but very pretty effects can be made by growing six or seven plants in a larger pot, say nine- or ten-inch and training them over a trellis.
VINES GROWN FOR FOLIAGE
The smilax of the florists (Asparagus medeoloides, also known as Myrsi phyllum asparagoides) is also one of the best vines for the amateur's window garden. Planted in boxes, it can be trained to the window cases. The shaded places in the window garden are admirably adapted .to its necessities, so it can be used where other green plants refuse to grow. The plant will make a growth ten feet long, and must have a string to climb upon. The foliage is a dark, glossy green, and there are single white flowers in winter, which are very fragrant. The seeds must be sown in January or February, and when the young plants are two or three inches high, and are making their characteristic leaves, transplant them singly to two-inch pots. In May they will need shifting to three-inch pots.
July is the time when the florists plant them out in beds in the greenhouse, but in the window garden, where a bed is not possible, I use a long, narrow box, six inches wide, as much deep, and two feet long. In this five plants are set. This is a little closer than the florists plant them, but as I have only a single row, it gives them plenty of room for development. The soil should be very rich — a fibrous loam, to which is added half-rotted cow manure and sand, one part each to three parts of loam.
The strings must be arranged just as soon as the seedlings are planted. The best material for this, because of its strength and colour, is the green smilax string used by florists, from whom it may be bought. Should you desire to use the smilax for festooning else-where about the house, the strings with the twining vine may be cut, and the roots will immediately start a new growth of stem. Make a new sowing of seed each year, as it does not pay to hold the plants over from one year to another. They need a night temperature of 50 degrees to 65 degrees.
ASPARAGUS THIRTY FEET HIGH
The most popular of the so-called asparagus ferns, A. plumosus, var. nanus, may be trained in vine form, too. I have seen this "dwarf"growing to the height of thirty or forty feet, with great stems like tangled creepers in a jungle. This is the best variety, because it can be used for short sprays, as a decorative pot plant, or as a vine. There is no foliage more beautiful than the delicate, light green, feathery sprays of this asparagus, and yet, in spite of its fairy-lace appearance, when cut it keeps both its colour and freshness for a very long time.
This plant is a slow grower, and it is important to have fresh seed. Sow in a good, light seed soil — i. e., one having plenty of leafmould and sand in it. When the young plants begin to make good root growth, transplant to three or four inch pots. This size pot will be sufficiently large for the plants all next winter. If the growth is too long and straggly, pinch back, as is necessary. In the summer time you must decide how you wish to grow the plants — as dwarfs, or as vines.
To grow a handsome pot plant which can be used for decoration anywhere in the house, shift the young plants to a five or six inch pot, and use a good, rich, but well-drained soil. When the new growths are a foot or so long pinch out the ends. This will keep the plant dwarfed and shapely.
To grow as a vine, plant in boxes just like smilax, and be very particular that the soil and boxes are well drained.
The seeds of this asparagus are expensive, because it does not fruit freely.
IN FLOWER ALL THE YEAR
Of course you will want flowers, as well as green foliage. Perhaps the very best all-purpose flowering plant is Primula obconica, var. grandiflora, which is not tender, and blooms the whole twelve months. It is the most graceful of all primroses. Its large, single flowers are borne in clusters on the tops of stems which are four to ten inches high, and their pale, white cheeks just tinged with blue or blushed with rose. In well-grown specimens the individual flowers are often an inch and a half across. The leaves are almost round, sometimes four inches in diameter, borne on long stems, and forming a rosette supporting the flower stalks. The hairs on the leaves are irritating or poisonous to some people, which accounts to some extent for the plant not being more popular. Certainly it will grow in a more varied range of temperature, and flower longer than any other house plant.
Sow the seed any time from January to March. It may be sown later, but unless you have a coldframe in which to shade the seedlings, the young plants will be more difficult to manage. By May the seedlings should be ready for thumb-pots. A few days after potting, give abundance of air — though keep shaded — and never allow them to get dry. Syringe them on bright mornings, and after the middle of September keep the temperature about 50 degrees at night. In potting and repotting — they will require several shifts — take care not to press into firmly about the roots, and not to cover the crowns of the plants.
FLOWERS FoR FRAGRANCE
The one plant which will give the greatest amount of satisfaction on more distinct counts than any other in the window is the cherry pie (Heliotropium Peruvianum). The beautiful purple colour of the flowers combined with the sweet, spicy perfume (whence its English name) and the long period of bloom, combine to make this an ideal window garden plant.
Originally the heliotrope flowers were violet coloured and borne in trusses about two inches across, but now, after much improvement by breeding, they are also to be found in several shades of purple and even white, and the individual trusses six inches across.
Grown in pots or boxes, a plant will ultimately cover a space about eighteen inches square, and attain a height of a foot or fifteen inches.
If you want to do something a little unusual, grow a few of the plants to a tree form. When handled this way four crops of flowers can be had from one plant from May to October. Such plants are extremely useful for hall and porch decoration.
Sow the seeds at any time from February to May, and grow the plants in pots all summer, as the heliotrope objects to removal or any interference with its roots.
If the plants are kept in the dwelling house during the summer, give as cool and moist an atmosphere as possible, for though they like sunlight, too much dry heat will scorch both leaves and flowers. Pinch back the plants wanted for winter flowers so as to give them a stocky form and to prevent them from making flowers in the summer. If possible, plunge them outside in the flower border, turning them once in a while to prevent their rooting through the hole in the bottom of the pot. Take them into the house upon the approach of cold weather. Plunging means setting the potted plant in the soil, up to the rim of the pot. This keeps the roots cool.
SUCCESS WITH MIGNONETTE
Measured by the fragrance alone I believe that the mignonette (Reseda odorata) is by far the best window plant for home raising. The pyramidal flower heads are unattractive in colour, but they exhale a most delicious odour — there is nothing else just like it.
Mignonette is very hard to transplant; indeed it is impossible to do it without giving the plants a check, and the secret of growing good mignonette lies in growing it on without a check at any stage of its growth. For winter bloom sow the seeds in July, August, or September. July-sown seed will bloom in November. Instead of sowing in fiats sow directly in pots.
Prepare as described for flats as many two-inch pots as you wish plants to grow. Make a slight depression in the soil in the centre of each and drop into it two or three seeds, covering lightly with soil. When the seed has germinated (about two weeks) thin to one plant to a pot, retaining the strongest. When the pot has become filled with roots shift to four-inch pots and as soon as these are full of roots shift to eight-inch pots. When giving this last shift put in a two-inch layer of drainage. Be very careful not to over water or the soil will sour; but, on the other hand, mignonette must never get dry that would cause a check. For the same reason never allow the plants to become potbound.
When the plants get about four inches high, pinch out the centre of the middle shoot. Two or three new shoots will come out from the stem, and these, with the five or six which have developed, will make a well-shaped plant. Pinch out any other shoots which may start. When the plants get about six inches high, they will need staking. For this, use small, round stakes that will be inconspicuous — birch or willow twigs are excellent for this — putting one to each stem.
When the plants get about ten inches high, and before the flower heads show, pinch out the tops of the stems so as to induce all the shoots to flower at the same time. When the flower buds commence to show, give the plants weak manure water for about a week, if the pots are well filled with roots. As the buds develop, give it oftener — say about twice a week. If you have grown the mignonette carefully without a check, there is no reason why you should not have nice plants, bearing anywhere from a dozen to fifteen good spikes. The mignonette is a cool-loving plant, and it is said that plants grown in a cool temperature will produce more fragrant flowers than those grown in a warm temperature.
I have never grown, nor have I seen, snapdragon (Antirrhinum majus) in the house, but I would not hesitate to try it. In a cool greenhouse it is almost as easy to grow as weeds. It can be had in beautiful spikes a foot long, and in white, yellow, and red.
For flowers the following winter, sow the seed in July, or early in August, and grow on the plants as rapidly as possible, shifting them from the two inch pots in which they are started to four inch and later five or six inch, when they demand it.
THE LOVELY CYCLAMEN
No plant gives better satisfaction than the Persian cyclamen (C. latifolium). It is well worth trying in the window garden. Its flowers last a long time in good condition, and it has a wealth of colour._ The flowers are very curiously shaped, reminding one of its relative the shooting star (Dodecatheon).
They are white or varying in different shades of pink to very dark rose colour, with a purple blotch at the mouth. There is a form the petals of which have fringed edges.
These are best grown from seed, and so constant are some of the strains that one can buy named forms which come true. The largest flowered form is called giganteum, but the large flowers are produced at the expense of quantity, so the amateur would better content himself with the good strain of a smaller flowered form. It takes fifteen months to grow the cyclamens from seed to flower, and they must never receive a check. When through flowering throw the bulbs away; they do not do well when held over.
For spring Rowers the seeds are sown in November or December. These are slow to appear above ground because a little bulb is formed before the first leaf shows. As soon as two leaves have been made, trans-plant the seedlings to four or five inch pots, placing several in a pot, and putting them near the outside. These young seedlings are very apt to suffer from too much water and over-potting — when the plants have about half a dozen leaves shift them to three inch pots. They will not need another shift until the middle of summer when I should put them into four inch pots. In September shift them to five or six inch pots, in which they will flower. The best soil is a good fibrous loam and leafmould, well-decayed horse manure, and sand in about equal parts.
Other plants which may be grown from seed successfully in the house are:
Flowering maple, Abutilon striatum; Floss flower, Ageratum Mexican urn; Amethyst, Browallia demissa (elata); Chimney bell flower, Campanula pyramidalis; Cigar plant, Cuphea platycentra; Trumpet flower, Datura cornucopia; Dragon plant, Draccena indivisa; Balsam, Impatiens Balsamina; Cypress vine, I pomoea Quamoclit; Mina, Ipomoea versicolor (Mina lobata); Lemon verbena, Lippia citriodora; Ice plant, Mesembryanthemum crystallinum; Wax plant, Mesembryanthemum tricolor. Another wax plant, Hoya carnosa, is propagated by division or by cuttings. Fig marigold,
Mesembryanthemum cordifolium, var. variegatum; Musk plant, Mimulus moschatus; Flowering tobacco, Nicotiana affinis; Nicotiana sylvestris, Nicotiana Sanderce; Oxlip, Primula elatior; Chinese primrose, Primula Sinensis; Baby primrose, Primula Forbesi; Scarlet sage, Salvia splendens; Wishbone plant, Torenia Fournieri; Canary-bird vine, Tropoeolum Canariense; Madagascar periwinkle, Vinca rosea; White periwinkle, Vinca rosea, var. alba; Pansy, Viola tricolor.