Begonias in Flower Garden

New Zealand Journal of Agriculture, Volume 99, Issue 4, 15 October 1959, Page 383

Begonias in Flower Garden

By

J. S. SAY,

Horticulturist, Department of Agriculture. Auckland

MASS displays of tuberous begonias growing in pots and hanging baskets are the main feature in the glasshouses of many public and private gardens during summer. Their perfect shape and delicate texture combined with a wonderful range of colours make them one of the most popular of pot plants. In addition to the large-flowered tuberous begonias there are a number of other flowering types suitable for glasshouse, garden, and indoor decoration which are not so well known. Two in particular are well worth growing, Begonia multiflora, which flowers in the summer, and Begonia Gloire de Lorraine, which will make a bright show during the early winter.

Tuberous Regonias TUBEROUS begonias can be grown to perfection in a glasshouse, sunporch, or on a sheltered veranda. A very sheltered lath house or shade house makes a suitable home for them in many districts and they make good bedding plants in a favourable corner in the open ground. They are not entirely satisfactory as house plants, as they sometimes do not flower freely. Propagation Tuberous begonias may be propagated by seeds or cuttings. Anyone

who has not grown tuberous begonias before would be advised to start with bought tubers, for seeds are a little difficult, especially without a glasshouse or frame. Division of old tubers is also possible, but not generally recommended. Seed As the seed is extremely fine and the young seedlings are very small and difficult to handle, some skill and good facilities are needed to be really successful with this method. Seed may be sown any time from late winter in a glasshouse (heated in cold districts) to November or

December. Early and mid-season sowing will produce good plants which will flower during summer and early autumn, but late sowings are unlikely to give any flowers. Some specialist growers sow in late autumn, but this is not generally recommended, as overwintering the small plants is a problem. A John Innes seed sowing compost consisting of 2 parts of soil, 1 part of sand, and 1 part of mould (or peat or good compost), with the addition of lg oz of superphosphate and t oz of lime per bushel, is suitable, though

some prefer other mixtures. Mixtures of equal parts of soil and sand and one or 2 parts of leafmould and 1 part of sand have given good results. The soil should be sterilised if possible for disease and weed control. Compost can introduce many weed seeds which germinate and grow much more rapidly than the begonias, and it is better avoided if leafmould or peat can be obtained. °

The ingredients should be put through a | in. sieve and thoroughly mixed. The mixture should be lightly firmed in the seed tray or pot and, after the surface has been made level, it should be topped off with some of the mixture through a very fine sieve. The seed should be sown thinly and not covered with soil. The box or pot should be covered with glass and paper. As the seed is very easily washed away, watering is better done by soaking the box in water, unless a can with a very fine rose is used. When the seeds germinate lift the glass and paper an inch or so and remove after a few days. Some shading on the glasshouse or frame will be necessary in spring and summer. As much air as possible should be given, because moist, stagnant conditions encourage fungi which cause damping off and rotting.

The seedlings are very small, making them difficult to handle, but they should be pricked out into other boxes about 2 in. apart as soon as possible. They are often easier to handle with a stick with a small V cut in the end than with the fingers. Whatever system is used the seedlings should be treated gently. The seed sowing mixture can be used, but the fertilisers can be increased to 1| oz of superphosphate, 1| oz of blood and bone, J oz of potash, and f- oz of lime per bushel.

When about 3 in. high the seedlings will be ready for potting up into 3 in. or . 4 in. pots and later they will have to be potted on to larger ones or flowering. Early sowings will probably reach 7 in. or 8 in. pot size. A John Innes potting mixture is suitable. It consists of 7 parts of soil, 3 parts of leafmould (peat or compost), and 2 parts of sand to which is added the fertilisers mentioned above for pricking out.

Many growers prefer a lighter and more open mixture made by adding 1 or 2 extra parts of leafmould and sand. The addition of some well rotted animal manure (cow, horse, or sheep) is favoured by many growers.

Cuttings

Cuttings, made from the shoots arising from the tubers when they break into growth, root easily. They are usually made when the shoots are about 2 to 3 in. long and are rooted in sand or a mixture of sand and leafmould. If cuttings are taken very early, bottom heat is of great assis-

tance, but later they can be rooted under normal glasshouse or frame conditions. After rooting they should be potted up into 3 in. or 4 in. pots in the mixture given for seedlings and later into larger pots. Starting Tubers Tubers may be started into growth in late winter if a glasshouse is used (heated in cold districts) or left until spring or early summer. It is not advisable to start them too early unless adequate facilities are available. The flowering season can be extended by starting some tubers early and others later. Where cuttings are required it is as well to start the tubers as early as practicable to give the cuttings a long season to develop, flower, and make a tuber. A mixture of equal parts of sieved leafmould and sand makes a good medium. It should be moist but not wet. The mixture is put in a shallow box, lightly firmed, and the tubers pushed down into it and then just covered with more of the mixture. The box should be put in a warm place, but if heat is used it should not be forcing, or weak sappy growth will result. Sometimes it is difficult to tell the top of the tubers from the bottom. The top is usually concave. If any tubers appear to be slow in breaking into growth, they should be lifted and examined, for they may have been set upside down. Before tubers are put into the mixture they should be carefully examined. Rotted parts should be cut out and the cut surface dusted with sulphur. . Roots usually do not start to grow until the top growth is well advanced. The tubers should not be potted up until they have a mass of well developed roots. Except for basket varieties only one shoot should be allowed to develop on small tubers, but two or three may be left on three- or four-year-olds. In general the finest flowers are produced by one- or two-year-old tubers with a single stem. The other shoots can be used as cuttings if required. If not, they should be rubbed off as soon as they begin to grow.

For potting up rooted tubers some gardeners believe in potting into small pots (4 in. or 5 in.) and .then potting on into 6 in., 7 in., or 8 in. as required; others pot direct into large pots. Both methods are satisfactory. The former has the advantage of taking up less room for a month or so, but means double handling; the latter requires a little more care in watering, but is a great time saver. When potting the top of the tuber should be very slightly below the soil level.

Cuiture

The culture of plants from seed, cuttings, or tubers is the same once they have been potted up. High temperatures should be avoided, the most satisfactory range being about 50 to

70 degrees F. Where heat is used early in the season it should not be forcing. In summer begonias need plenty of ventilation and some shade. Too heavy shade, especially with high temperatures, will promote a soft, sappy growth which is very liable to disease and will also have an adverse effect on flowering.

Watering should be done with care. Water thoroughly and then leave until the pots show signs of dryness. A pot in need of water will give a ringing sound when struck sharply with the knuckles or a small wooden mallet. When wet it gives a dull sound.

Staking is always, necessary and should be done at an early stage. Thin bamboo canes make good stakes and are inconspicuous. A thin wire bent into the shape of a Y with a very long tail is useful for propping up the flowers when necessary.

Until the plants are well developed remove the flower buds as they appear. The first few flowers produced by immature plants are usually small and their loss is more than compensated by increased vigour of the plants and better flowers later. Disbudding can regulate the time of flowering and can be done where a mass display is required at a certain time. The two small female flowers borne on either side of the large showy male flower

should be removed. Old flowers should be removed as they fade and not be allowed to drop and rot on the soil or leaves, as the fungus attacking them will soon spread to the stem and leaves. Light applications of liquid manure can be given as they come into flower if the plants are pot bound. Overfeeding will induce weak growth which will not hold the flowers up well and which is very liable to disease. Plants have to be dried off after flowering by gradually reduced watering. It should not be stopped suddenly. As soon as the tops have dried off completely the tubers can be knocked out of the pots and shaken free of soil, dusted with thiram, and put into winter storage. A great many tubers are lost during the storage period. If kept too wet, they are liable to rot or start into growth before needed. If too dry and warm, they shrivel and die. They may be spread out in shallow boxes or partly buried in dry sand, perlite, leafmould, or peat and placed in a well ventilated, cool, darkened position. Examination at fairly frequent intervals is advisable so that any trouble can be checked before it becomes serious. Some growers leave the tubers in the soil , in the pots laid on their sides in a dry position. Though this works well, it has the disadvantage that the tubers cannot be examined easily. Shade House Culture Especially in the warmer districts tuberous begonias can be grown well in lath or shade houses. Growth is usually much sturdier than in glass-

houses, for the plants seem to like the cooler, airy position. They should not be started into growth too early, for late frosts can do much damage. Another big problem is wind. Firm staking is essential and if possible the pots themselves should be plunged or secured in some other way to prevent them from blowing over. Polythene lining on the windward side is a help, but it is usually an unexpected wind from another quarter that does the most damage. Outdoor Culture Tuberous begonias in the right spot will make a wonderful show in the garden. A . position completely sheltered from wind and receiving dappled shade from trees; is ideal. Plenty of leafmould' and well rotted manure worked into the soil will give good drainage and a cool, moist root run. For best results the plants should be well established in pots and then hardened off before planting out. As House Plants Tuberous begonias are frequently not satisfactory for indoor decoration. Unless they are in a room which receives plenty of light, they are likely to be weak and drawn and will not flower, but they should not be put in direct sun. Plants brought into the house when in full flower often drop their flowers almost immediately and do not bear any more. This is caused by the rapid change of conditions, for example from a glasshouse to the poorer light and drier conditions of a room. Other than placing them in the best possible position little can be done to bring them into flower again. They

should not be fed with liquid manures or be watered too much or too often, as this is more likely to add to the trouble. Basket Begonias Basket begonias are pendulous forms of tuberous begonias and treatment is almost identical. The only differences are that several shoots can be left on each tuber and the female flowers need not be removed, as the maximum display of colour is needed rather than perfection of individual flowers. Best results will be obtained if the tubers are started up in the usual way and then potted into 4 in. or 5 in. pots. Once they have become well established and are growing strongly they can be put into baskets. Three plants spaced round the basket will give quicker and far better coverage. Begonia multiflora Begonia multiflora is a tuberous type with a dwarf bushy habit and during summer produces masses of flowers similar to but much smaller than the larger-flowered tuberous varieties. There is a good range of colours in singles and doubles. As they are hybrids, propagation from seed is not satisfactory, but they can be raised easily from cuttings in the same way as large-flowered tuberous begonias. They make good bedding and edging plants and will stand sunnier and more exposed positions than the large type.

Culture is the same as for tuberous begonias, but many shoots may be left to each tuber and no disbudding, is needed.

Gloire de Lorraine Begonias

The winter-flowering Gloire de Lorraine begonias are comparatively little known in New Zealand. They have thin, wiry stems, a compact bushy habit of growth, and when well grown are completely smothered in small flowers in late autumn and early winter. The variety Gloire de Lorraine from which the group takes its name has pink flowers and is the one most frequently seen. Other varieties have white, deep pink,, and carmine flowers. The leaves are almost circular, shining, and are usually pale green except in some varieties which have a reddish tinge.

As Gloire de Lorraine begonias are infertile hybrids, they can be propagated only by vegetative means. Ordinary stem cuttings or leaf cuttings may be used. They are usually taken soon after flowering is finished in late winter or may be left until early spring and are rooted in sand or a mixture of sand and leafmould. Unless bottom heat is available, rooting may not be satisfactory, especially if the cuttings are taken early.

. Leaf cuttings usually make the best plants. The leaves should be cut off with an inch or more of leaf stem. The new plant rises from the base of the stem and not from the leaf as in Rex begonias. The stem should be inserted into the rooting medium to about half its length. After rooting they can be potted up into 3 in. pots, but potting should not be done until the shoot has also developed. The potting compost recommended for tuberous begonias is suitable.

During summer they require some shade, moderate temperatures, and not too much water. To keep' them growing strongly a little liquid feed may be given, but overfeeding 1 will cause weak sappy growth. By late autumn they should be in the pots in which they will flower. A well grown plant will fill a 7 in. or 8 in. pot or pan. The new shallow pots make excellent containers. Staking is usually necessary and the best way is to insert some very thin canes round the edge of the pot and tie them together to form a low cone. This will hold the plant up with the minimum of tying and it will form a dense, compact mass. Heat in late autumn-winter is desirable in all but the warmest districts. A minimum winter temperature of 50 to 55 degrees F is required.

After flowering they should be cut back to about half their height and watering reduced, but they should not be dried off. The stems and leaves

removed may be used as cuttings, but better stem cuttings will be obtained from the young growths in spring. When growth begins the old plants will need repotting. Plants are not usually worth keeping after three years, the best display being given by plants in their second year. Other Species A little - known summer - flowering kind which is sometimes available is the hollyhock begonia. There is a little doubt about its correct name. It is usually known as B. martiana or B. gracilis martiana. Other similar varieties with which it could be

confused are B. gracilis annulata and B. gracilis diverstfolia.

It is a tuberous kind which produces a single upright stem 2 to 3 ft high. The pink flowers about 1 in. across are clustered all the way up the stem, hence its common name, and are borne for about three months. Culture is the same as for ordinary tuberous begonias. This group of begonias has the peculiar habit of producing clusters of six to 12 small tubers about 1/16 in. diameter in the axils of the leaves after flowering. These can be sown like seeds in winter in a heated glasshouse or in spring. Another seldom seen species which is useful for glasshouse decoration in late autumn-early winter is B. froebeli. It grows to about 12 in. with large hairy leaves, and loose drooping heads of bright scarlet flowers about 1 in. across. It is a tuberous species which is more or less dormant in summer. It is sometimes treated like an annual, for it grows readily from seed and will flower in one season. The many varieties of fibrous rooted B. semperfiorens are well known and used extensively as summer-bedding plants. Not so well known but becoming very popular are the double forms. The pink variety Gustav Lund or Westport Beauty has been available for some years and several other colours have recently been put on the market. They are just as easy to grow as the ordinary bedding types and can be used in the open garden or as pot plants in the glasshouse or indoors. They flower most of the year

round in frost-free areas or under glass. In cold areas they need winter protection. They are easily propagated by cuttings taken at almost any time of the year or by dividing old clumps. Many other begonias grown primarily for their foliage also produce showy and attractive flowers. A number of these were described in an article in the December 1958 issue of “The Journal”. Pests and Diseases Begonias are relatively free of serious pests and diseases. Rotting of stems and leaves of tuberous kinds can be serious where growing conditions are not good. At the seed-box stage overcrowding, overwatering, and too humid atmosphere make the young seedlings very susceptible to damping off. Later, high temperatures, humid conditions, too much shade, and poor ventilation cause a soft growth readily attacked by stem and leaf rotting fungi, particularly botrytis. Good growing conditions and hygiene are the best preventives. Thiram will help to control all these fungus diseases, but will not cure them. Cyclamen mites sometimes are a serious pest. They are very small and can barely be seen with the naked eye. They cause serious distortion of the leaves and growing tips. Malathion is the best control. Mealy bugs and white flies may be controlled with DDT and aphids by nicotine sulphate.

Work for November

Staking of plants should be included among the tasks to be attended to in November, with the possibility of seasonal gales. Staking should

be done as plants develop. The ultimate height of most plants is known and they should be staked accordingly. Plants are growing quickly at this season and will soon hide the stake. Durable metal stakes are now available. If shallowrooted plants such as banksias, leucodendrons, proteas, dryandras, and flowering crab apples on dwarf rootstocks were not staked at planting, they should be attended to. Dahlias are best staked at planting so that the tubers are not damaged when the stake is inserted. Twiggy pieces of bamboo can be used among clumps of geums, potentillias, and other sprawling plants to give unobtrusive support. Climbing Plants Supports should be provided without delay for all climbing plants. Climbers are often planted to help screen paling fences. For lighter types of climbers plastic coated flex can be strung against the woodwork. At the

base of some wooden fences a space is sometimes left so that the bottom wood does not rot through contact with the soil. A draught through such a gap is often damaging to young plants, and boards placed along the gap, at least until the plants become established, will be worth while. Strong-growing climbers such as vitis, or Celastrus scandens, should be tied in as they develop, especially in windy areas. Seed of some climbers, including Cobea scandens, ipomea (morning glory), and Mina lobata can

be sown in warm positions to give quick cover. Ipomea seed should be soaked in water for a day before planting. Seedlings In flower borders gaps can be worked to a fine tilth for sowing the seed of annuals, which develop quickly. Seed sown earlier should be thinned out to give the plants a chance to develop. Thinnings could

be transplanted into other gaps. In the back of the border seed of helianthus (sunflowers) helichrysum (everlasting daisies), and ricinus (castor oil plant) can be sown early this month to fill the gaps quickly. Calendulas if sown now could be used to fill gaps which appear in January. Wallflowers, anemones, polyanthus, sweet williams, and biennials including Canterbury bells can now be sown in boxes to germinate and develop for flowering next spring and summer.

Flower Arrangement Several plants which are particularly useful for cutting and. Use in flower arrangements can be raised from seed sown at this time. Ornamental gourds can be sown as a ground cover among shrubs on a sunny bank. Seedlings of ornamental crimson beet can be pricked out early and look well as a sunny border plant alternated with the grey leaved Centaurea candidissima. Molucella (bells of Ireland) is often better if sown thinly where it is to flower. Euphorbia marginata (snow on the mountain) can also be broadcast in the open ground. If left, this plant will reseed itself each season. Ornamental kale and corn can also be sown. The perennial plant Physalis franchetti has bright orange calyces persisting throughout winter and can

Clematis jackmani, one of the varie- ' ties which flowers at this time of the year and which should have an adequate trellis over which to climb. be grown from seed sown now. It develops a widespread root system which may affect other plants. Bedding Plants If it is not possible to plant out boxed seedlings before the roots have filled the soil in the boxes, they should be given weak liquid feed; otherwise they will become yellow and starved. The day before plants are set out the boxes should be well watered so that the leaves are turgid and better able to stand transplanting. The soil will also adhere to the roots. If the bed is dry, it should be soaked a day or two before planting out or immediately after. If hot weather occurs and the plants droop, a light hosing could be given in the evenings as well. Contrasting colour schemes such as orange marigolds with blue ageratum, Verbena venosa among pale African marigolds, or bright red geraniums set against their background of dark green foliage make dramatic yet harmonious bedding schemes. Very closely related colour schemes have a more restful effect and could be used in secluded areas.

Bulbous Plants ' . ' ' The corms .of cyclamen in pots should be given less water over

summer, but should not be dried off completely. Old pot plants can be placed on their side and on the cool side of the house. Young cyclamen seedlings can be pricked off into pots and should be kept growing over summer. Narcissus bulbs can be lifted every third year as the foliage fades. As a precaution soak all bulbs for 10 minutes immediately after lifting in aldrin emulsion at 4 oz to 2| gallons of water. Experiments have shown that this will kill any bulb fly which may be present and protect the bulb for the season. Bulbs should then be dried off quickly in a warm but sunless place outdoors. Cannas, crinums, sprekelias, clivias, and tigridia bulbs should all be planted as soon as possible. Anemones and Freesias Anemones and freesias can both be grown from seed sown at this time of the year. To obtain early flowers it is probably better to use small corms of anemones and these could be planted 2 in. deep. If cloches are available, the corms should be planted in double rows and covered in April for flowering in June-July.

Freesias grown from seed are usually free of disease. The seed will germinate more easily by rubbing in sand to remove the oily coating. This

allows the entry of moisture. The seed should then be mixed with moist sand and kept in a warm dark place. If placed in a glass jar, it is possible to see the white sprouts appear in about a month’s time, when the germinating seed can then be sown thinly in boxes. Dahlias and Chrysanthemums Dahlias can be planted now in all districts. In the milder districts dahlias which have been left overwinter in the ground will be shooting. If it is not desired to increase the planting by division, the shoots on vigorous plants should be thinned down to three or four as early as possible. A dressing of 4 oz of mixed fertiliser to each plant can now be given. A mixture of 3 parts of blood and bone, 2 parts of superphosphate, and 1 part of potash would be suitable for both dahlias and chrysanthemums. Rooted cuttings of chrysanthemums can be planted out early this month. Here again, thinning of shoots from established clumps is desirable. The remaining growths should have the top of the stem removed when they reach 8 in. and again when a further 6 in. of growth has been made. The clumps should be kept growing healthily so that they are less likely to succumb to pests and diseases. Insect Pests Springtails, which are lively greyishwhite insects, can damage germinating seedlings and in damp conditions where plants like sweet william lie close to the ground they are often associated with the rotting of plants. Where this is so decaying matter should be removed and the soil area watered with 1 teaspoon of nicotine sulphate to 1 gallon of water to which soft soap has been added. Aldrin at 1 oz to 120 sq. yd. or lindane 25 per cent wettable powder at 1 oz to 4 gallons of water , could also be used. Grass grub beetles will be flying in the evenings now and feeding especially on foliage of deciduous shrubs. These beetles lay their eggs in the soil and the young larvae hatch out in two to three weeks and begin eating the young roots of many plants. Soil which has been treated with 50 per cent DDT at 1 oz to 40 sq. yd. will not allow these pests to become established. Flower beds as well as lawns should be treated every second year when fertilisers are applied. Thrips can also cause damage by sucking the sap from many plants and causing a silvering effect. Escallonia, rhododendrons, lauristinus, and citrus are often attacked and DDT, lindane, or malathion in emulsion forms could, be used as a spray. Pruning Spring-flowering shrubs such as. Erica parkeri, Erica Dawn, Olearia.

gunniana Blue Gem, prostanthera, lilac, weigela, and early brooms can now be pruned. As the flowers fade, flowering branches should be cut back to two to three buds. This removal of seed heads is also an important factor in increasing the life of South African flowering plants such as proteas. Hedges should be clipped now and the refuse composted. It is especially important to trim newly planted hedges; otherwise they become leggy and bare at the base. It is difficult to encourage growth lower down later. Artemisia is a grey-foliaged plant which makes an attractive quickgrowing hedge. It should be clipped every two months over the growing season. Roses For show roses side shoots should be disbudded early, as soon as the buds grow apart. Such close examination of the buds will usually reveal any insects. A combination spray or dust should be applied throughout the season and the following are suitable: Dust 10 parts of 1 per cent or 2 per cent lindane dust 9 parts of flowers of sulphur 1 part of 50 per cent thiram or captan Spray 1 oz of captan or thiram 50 per cent J oz of colloidal sulphur 75 per cent powder t oz of malathion powder 4 gallons of water It is unwise to use the emulsion forms of sprays, as they have been known to cause damage to young growths. These mixtures are planned to kill insects already present and to prevent any damage from fungus diseases. To prevent disease it is necessary to spray or dust regularly every two weeks or after heavy rain. Lawns In young lawns, especially those which were sown with little soil preparation, weeds often come away strongly. An application of hormone weedkillers followed immediately by fertilisers will kill most weeds. On young lawns 1 fl. oz. of the potassium salt of MCPA should be mixed with water and spread over 100 sq. yd. This should be followed by 1 oz per sq. yd. of a mixture of 3 parts of sulphate of ammonia to 1 part of superphosphate, a dressing which should be repeated quarterly. Grass grubs should also be controlled and this subject is dealt with under the section Insect Pests. General Regularly weed flower beds. Weeds will be making rapid growth now and could rapidly outgrow some desirable plants.

Mulches should be used liberally round most shrubs and especially surface-rooting ones like camellia, hydrangea, rhododendron, and azalea. Mulching with sawdust can be used to control weeds in shrubberies and among bulbs. Nitrogen in the form of blood and bone or sulphate of ammonia should be applied at the same time. Flower heads should be removed as they fade to prolong the flowering season. Healthy material should be composted. Poor plants should be replaced where possible. If growth is distorted or streaked, the plant may be affected by a virus and should be burnt. Aubrietia, marguerite daisy, and perennial wallflower. sometimes become straggly. They should be trimmed back now to encourage young growth. Gladiolus should be staked as they develop. Bamboo canes are very suitable. Any plants which wilt or yellow should be dug out and burnt. Bulbs not yet planted should be dipped in Aretan at 1| oz to 4 gallons of water for 30 to 60 minutes before planting for autumn flowers. Pot plants should be turned occasionally to prevent them becoming lopsided. They should not be overfed with nitrogenous fertilisers or they may become sappy in growth and produce few flowers. If the ground is becoming very dry, trees and shrubs planted this season will benefit from a good soaking with the hose and then by a mulch.

By ROSALIE A. CAMPION, Horticultural Instructor, Department of Agriculture, Wellington

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Most summer-flowering subjects in the glasshouse are beginning to make their display. Attention should be paid to ventilation; watering, and feeding to bring the plants to perfection.

Temperatures should be kept as even as possible.

During hot weather houses should be damped down several times a day to prevent a dry, hot atmosphere which encourages the increase of many plant pests.

Fuchsias and begonias are two plants which grow well together, as both require shade. Fuchsias should not be placed in too large a pot, but benefit from liquid feeding. Begonias should be potted on as the roots fill the pots. The roots of well grown plants will usually fill a 7 in. pot eventually.

Seed of Primula malacoides and P. sinensis should be sown now to provide flowers next winter.

Plants such as crotons, palms, and asparagus which remain in the same sized pot for a long time will benefit from regular liquid feeding with I oz of sulphate of ammonia to a gallon of water.