The greenhouse must be kept clean and well aired. This month is appropriate for cleaning and repainting the greenhouse where Chrysanthemums have been flowered.

The interior of the house should be well scrubbed with disinfectant soap. White paint adds to the light of the interior.

Necessary repairs should be undertaken, at the same time make good all stages, and renew hooks, supports, etc., for climbing plants.

When airing the greenhouse at this time of year, see that the ventilators on the side away from the wind only are opened. Cold frames sheltering Violas, Antirrhinums and other hardy subjects may be left open during the day, closing them only when frost is severe.

For early flowering, the following seeds can be sown this month in a heated greenhouse: Antirrhinums, Amaryllis, Annual Carnations, Begonias, Cyclamen, Grevillea, Gloxinias, , Petunias, Scluzanthus, Verbena.

Early vegetables can also be sown now, including: Cauliflowers, Carrots, Lettuces, Leeks, Mustard and Cress and Onions.

Tomatoes can be sown in sterilized soil, and good soil prepared for use later in pots or the greenhouse border. All soil for tomatoes should be sterilized before use.

Seeds should be sown in boxes or seed pans supplied with good drainage and filled with especially prepared compost.

A good sowing compost consists of two parts good loam and one part leaf-mould, with the addition of sharp sand. Vary the amount of sand, according to the kind of seed; for delicate seeds that damp off easily, add more sand, and reduce the amount of leaf-mould.

Take cuttings of greenhouse Chrysanthemums as they become available. Cuttings are made of young shoots about 3 or 4 in. long. Insert them in sandy soil, in a propagator, or in pots with a bell glass over them. This will be removed when the cuttings have well rooted.

Buy Lily bulbs now. Pack them in moist coco-nut fibre in the greenhouse. They will lose the shrivelled appearance which is common to lilies on sale at this season, and will be fit for planting in the open garden when the weather breaks.

Lilies to buy tins month include Lilium auratum (gold-white), L. BatemannicB (red apricot), L. cordifolium (yellow-gold), L. hansonii (orange-brown), L. henryi (orange-red), L. leichllini (yellow) and L. tigrinum (orange-red), the popular Tiger Lily.

When watering plants in the greenhouse, use water of the same temperature as the greenhouse. Tap water is usually too cold. A rain-butt inside the house, connected to the gutters outside, is a useful source of supply.

Generally speaking, as little water as possible should be given to plants in winter.


The chief work to be done this month is in the care of young seedlings, and planting them out into boxes, which can stand over the hotbeds, or in the cold frame.

Early Lettuce and Onions can be thinned out in the frame. The}’ must not be “nursed,” or the crops will be poor.

Hotbeds can be made up this month. Daily attention must be given, to keep up the heat, fresh manure being added to the sides of the frame as the temperature falls.

The hotbed can be used for early supplies of Globe Artichokes, Tomatoes and Vegetable Marrow, all of which can be sown or started into growth this month.

Salad crops can also be raised in a hotbed.

Dahlias can be started in heat. Place the dahlias in shallow boxes of moist soil and do not allow them to dry out.

Begonias can be started by treating the tubers in the same way, or they can be started in moist coco-nut fibre.

Repot Fuchsias, and after repotting give them a little bottom heat.

Geraniums, too, can be given bottom heat this month, to induce new growth and cuttings taken from the plants that have been flowering all winter.

Other plants ready for propagation by cuttings this month are: Coleus, Heliotrope, Perpetual-flowering Carnations, Petunias.

Greenhouse plants are very subject to mildew at this time of year. An effective spray of ½ oz. of Liver of Sulphur in a gallon of tepid water is useful, but it must not touch white paint.

In spare moments, prepare composts for the rush of seed-sowing next month.

Different seeds need varying proportions of sand and leaf-mould, the more delicate seeds need more sand, otherwise they damp off. Strong growers find more nourishment in a leafy compost and will not need to be transplanted so quickly if the seed boxes are well supplied in this respect. Two parts fibrous loam, one part leaf-mould, and one part sand, all rubbed through a 1/2-in. mesh sieve are a good mixture for most seeds. The coarse siftings should form the middle layer of seed boxes, ie. between the crocks and the top compost. This improves drainage.


March is generally recognized as the seed-sowing month.

For a good show of Primulas in the winter, seeds should be sown now. Ordinary seed-sowing compost may be used, but care should be taken to add a good quantity of sand. Primulas are very apt to “ damp off.”

Cinerarias sown now will make a bright show on the winter and spring shelves of the greenhouse. They should be sown in gentle heat, in a compost of loam, leaf-mould, peat and sharp sand.

Sow half-hardy annuals for a show in the beds and borders in summer.

Some of the most popular half-hardy annuals to be sown this month include Asters, Petunias, Ten-week Stocks, Salpiglossis, Verbena, Nicotiana, Zinnias, Nemesias.

There is still time to start Begonias in the greenhouse, using moist soil or fibre for this purpose. Dahlias, too, can be started in the same way.

Both Dahlias and Begonias can also be raised from seed sown now.

Take more cuttings of early-flowering Chrysanthemums.

Winter Cherry (Solatium capsicastrum) can be propagated by cuttings.

Cannas should be well watered, to induce them to send out shoots, and potted up in good soil.

Peaches under glass should be thinned out now, one peach to every square foot of wall space being quite sufficient.

Ventilation is very important under glass this month, especially among vegetables growing under glass.

Hardy ferns can be raised now in the greenhouse by putting the spores (the brown dust on the back of the leaves) on to small sandstones in a damp, warm atmosphere.

Now that frosts are not so frequent, and the weather is warmer, seedling plants such as Petunias and Cosmea, grown in the greenhouse for bedding out, can be potted singly in gritty soil and transferred to frames.

Pansies and Violas and similar hardy plants can be moved from the frames to the open borders to make room for the greenhouse seedlings.

Bulbs which have been grown for indoor decoration and have finished blooming can be planted in the borders, or in a part of the wall garden. They may flower another season, or miss a season and then send up flower spikes again.


Give more air and light to all seedlings. The more air the seedlings get, the sturdier plants they will make.

Cuttings that have rooted should also be given all the air and light possible.

Take boxes of young plants out of the frames and stand them in the open garden for a few days to harden. They should be returned to the frame at night if frosts threaten.

Pinch out just the tip from bedding plants which are wanted bushy and even for formal planting.

Seeds of Balsam, Celosia, Dahlias, Gloxinias, Lobelia, Petunia and Zinnias can be sown now, in the usual seed-sowing compost.

Sow Gourds, Marrows, Pumpkins and Ridge Cucumbers. These need a sandy soil with a liberal supply of leaf-mould.

They can be kept in the cold frame in a close atmosphere for a time, but soon as the seed germinates more air can be given. Always cover the frame at night.

All frames and house ventilators can be opened for a time during the day, except when winds are troublesome, extending the period as the month goes on, and brighter weather occurs.

Grape vines under glass can be pinched back now. Frequent syringing is desirable. The atmosphere should be kept warm and moist, and sudden changes avoided.

Any seedlings that become straggly and drawn should be pinched back now, to encourage side growth. Put them nearer the glass and give more ventilation to make the plants sturdier.

If necessary, Hydrangeas that have flowered can be repotted now. Cuttings can also be taken and inserted in a compost of loam, leaf-mould and sand.

For early strawberries, pot up some strong plants now. The plants should be well watered, and a temperature of 40-50° maintained.

French Beans may be sown in pots early this month for an early crop. A fairly even temperature of 55° is necessary for their cultivation.


As each batch of seedlings and rooted cuttings is planted out, clean the empty places thoroughly, and repaint where necessary, in readiness for the next batch of plants.

Plants not yet trusted to the open garden should be hardened off gradually.

If seedlings appear to be damping off, dust immediately with Flowers of Sulphur, and give less water, especially avoiding overhead watering. See that sunshine does not scorch young seedlings; frame lights are often best removed entirely during the day, and replaced at night.

French Beans raised in pots may be planted out into cold frames, allowing about in. between the rows.

Chrysanthemums and Perpetual Flowering Carnations can be potted up.

Repot Azaleas as required.

Layer Malmaison Carnations.

When Tomatoes grown under glass begin to set fruits, feed with weak doses of liquid manure, and top dress with tomato fertilizer.

Keep a dryish atmosphere round Tomatoes in flower.

Tomatoes can be sown now for winter supplies.

Shrubs in the greenhouse intended for summer bedding should be hardened off now.

It is safe to keep a temperature of 65° during the day and not less than 45° at night for houses where half-hardy plants and shrubs are being grown.

Regular attention must be given to watering and spraying in the greenhouse now that days are warmer.


Artificial heat can now be dispensed with in the cool greenhouse.

Azaleas and Camellias need a sturdy growing heat while they are making wood.

The half-hardy annuals, and other bedding plants, such as Dahlias and Geraniums, should be ready for beds and borders now.

Young Dahlia plants attract slugs, but as “Slugs prefer Lettuce” it is a good plan to put a few unwanted lettuce seedlings between the Dahlias as these are put out in their permanent quarters.

Tender shrubs in pots may stand in the open during fine days. This gives the gardener an opportunity to clean up under glass and wash down staging, etc.

Fumigation and syringing must be done immediately if insect pests are seen in the greenhouse.

Chrysanthemums require to be repotted fairly frequently, using larger pots as soon as the roots fill the smaller sizes. The pots should still stand in the open, the stakes being secured to supports, so that winds do not blow the pots over.

Grapes should be thinned out this month. A pair of sharp-pointed scissors is best for the purpose.

Herbaceous Calceolarias and Primulas (sikkimensis and others) can be sown this month.

Primulas in particular require a sandy soil for seed boxes.

All seedlings should be pricked off as soon as the second pair of leaves show themselves.

Bright sunshine should be avoided, and an even temperature maintained.

While watering is essential, too much will encourage “damping off.” The safest way to moisten seed pans is by immersion in tepid water.

Tomatoes should not be allowed to make side shoots; plants in flower should be tapped lightly about midday. This jerks the pollen dust on to the pistil, and encourages fruit setting.


Now that all the summer bedding-out plants have gone from the frames and greenhouses, opportunity should be taken to clean these and do repairs that are needed.

The frames should be repainted, and any broken giass replaced.

Greenhouses should be painted and repaired, including repairs to staging and flooring. Fresh shingle, shell, or other material should be introduced as a good base for pot plants.

Water should be given fairly freely to all greenhouse plants. Peaches and Nectarines, if attacked by red spider, should be drenched by syringing with clear water in the evening.

Annuals used solely for greenhouse decoration may be sown this month. These include tender annuals such as Schizanthus and Browallia, and also hardy annuals such as Clarkia and Nasturtiums, for winter flowering. Cyclamen seed may also be sown now.

Cinerarias and Primulas sown last month should be ready for potting into small pots. Stand the pots in the cold frame, and be careful not to let strong sunlight scorch the seedlings. Frame lights should be removed whenever possible.

Cuttings may be taken now of Hydrangeas and Pelargoniums.

Azaleas, Camellias and Citrus may be grafted.

When Azaleas in pots have finished flowering, the wood should be allowed to ripen. The pots may be plunged in ashes, in the open, or plunged in the soil of the border, up to the pot rim.

Freesias should be potted now in a compost of sandy loam and dry cow manure. Plunge the pots in ashes in the same way as Azaleas. Darkness is not essential, as the bulbs are covered with soil.

Frames not needed for the cultivation of such plants as Tomatoes and Cucumbers need not be idle. Cuttings of Pinks, Arabis, Aubrietia, and other early flowers can be inserted and shaded. Seedlings of winter-flowering annuals can be sown and brought on in the frame.

Whitewash over the glass of the frames prevents the scorching of seedlings and cuttings.

An alternative method is to cover the glass with sheets of paper.


The dull days of winter will need to be brightened by house flowers-Bulbs should be bought now, and the first batches potted up in soil or fibre. Paper White Narcissus and Roman Hyacinths are undoubtedly the easiest bulbs to flower at Christmas, where only a frame or cold greenhouse is available.

Bedding plants, such as Antirrhinums, can be raised from seed sown now in boxes, and pricked out into a nursery bed or cold frame to stand the winter.

Calceolarias may be sown now in a compost of loam, leaf-mould, sand and dry cow manure. They like a cool and fairly moist atmosphere. Watering should be done carefully, to avoid washing the fine seeds out of the pans.

For a late crop of French Beans, sow now in a spare frame. Use the usual sowing compost, with a foundation of well-decayed manure.

Cauliflowers can be sown in the frame now, but they should not be “coddled” unduly.

Achimenes that have finished flowering should be stood outside in order that the tubers may ripen.

Pelargoniums should also be stood in the open to ripen the wood.

Gradually discontinue watering Lilies, as they die down.

Disbud Chrysanthemums.

Cut back climbing plants if they threaten to outgrow their positions.

Repot Azaleas as needed.

Syringe frequently all plants attacked by Red Spider.


As cooler nights occur, bring greenhouse plants that have been in the open garden during the summer back into the greenhouse.

Plants need less water in winter (ie. when they are resting) than in summer, and the amount of water given should be reduced accordingly.

Begonias should be allowed to die down now, but they can be left in their pots.

Achimenes and Gloxinias should be removed from their pots when the foliage has died down.

Parts of the greenhouse glass that have been whitewashed to keep out strong sunlight can now be cleaned.

As much air as possible should be allowed on warm days, but the houses must be closed at night to keep out frost.

Cuttings of herbaceous plants can be taken now and inserted in the cold frame.

Cuttings can also be taken of many kinds of trees and shrubs, these also being inserted in the cold frame. Conifers root readily in the frame at this season. Such cuttings should remain undisturbed until the spring.

French Beans can be sown, if a late crop is required, and heat available. They will be very welcome during the winter months.

Lettuce may be sown now for planting out in spring. Cos varieties are best to plant at this time of year.

For a succession of bloom, bring bulbs into more light and warmth in fortnightly batches.

It is still not too late to pot up spring-flowering bulbs in soil or fibre. Tulips, Lilies (Easter) and Iris (Spanish, English and Dutch) are all very showy and decorative on the greenhouse shelves.


Constant attention should be given to the ventilation of the greenhouse and cold frame.

Frosts will put in an appearance fairly frequently now; always close the greenhouse ventilators at night.

The following should be potted up now: Lilies, Lily of the Valley, Pansy cuttings for winter flowering, all hardy and half-hardy annuals for greenhouse decoration, flowering shrubs intended for forcing, and perennial plants used for summer bedding.

Plants that have been in the open or in the frames during the summer should be brought into the greenhouse now. These include Chrysanthemums for late flowering, seedling Cinerarias, Freesias, and other slightly tender bulbs.

Young seedlings of greenhouse annuals should be encouraged into bushy growth. To ensure this the tips should be pinched out now.

Perpetual flowering Carnations and Chrysanthemums should be disbudded now.

Cuttings can be taken of shrubby Calceolarias, Pansies, Penstemons, and Violas. They should be inserted in a suitable compost in boxes, and stood in the cold frame.

Cauliflower plants can be lifted, with a good ball of soil, into the cold frame to protect them from frost until they are required for table. If the plants have to remain outdoors a few leaves should be tied over the heads. This also keeps them clean.

Tomatoes and Mustard and Cress may be sown this month.

Primula seedlings should be kept cool and near the glass.

Some of the potted bulbs will be showing green tips; these can be brought into more light and heat as they progress. When the pots are removed from ashes, wash the outside of the bowls or pots to cleanse them, and dress the soil surface with shell or coloured chips.

Pelargoniums should be watered sparingly, and the leaves must be kept dry.

Fuchsias and Heliotropes should stand under the greenhouse staging, where they can remain all the winter. Fuchsias can be turned on their sides so that the pots dry out entirely.


For an early crop of new vegetables the following should be noted: Seakale and Rhubarb may be forced this month.

Tomato seedlings should be potted up.

Cauliflower seedlings can be planted in the frames.

Lettuce, Mustard and Cress and Radishes can be sown in heat.

French Beans can be sown now, these requiring a steady heat of not above 55°.

Nectarines and Peaches can be pruned now, and a top dressing will prove helpful.

For a succession of bloom, pot more bulbs this month. Some of those already potted can be brought into full light.

Lily of the Valley crowns potted up now will flower plentifully during the winter.

Arum Lilies should be grown in a temperature of 60° if good flowers are desired.


The greenhouse must be well ventilated, even in winter, but great care should be taken over this. The ventilators should be opened every morning about 9 o’clock, on the side away from the wind, closing them again after a few hours.

Water should be given very sparingly, in fact, watering should almost cease, except in special cases.

The stages should be kept scrupulously clean, and all dead leaves, etc., should be burned. This will prevent mildew.

For early flowering under glass, Dahlias may be started in heat at the end of the month.

Chrysanthemums should be cut down to about 3 in. from the soil level when they have finished flowering, and unwanted growths cut away altogether. A top dressing of leaf-mould and loam should then be put over the soil. This will encourage fresh growths. Water frequently, but do not give them too much water at a time.

Tomatoes can be sown now for an early supply, as can Beans.

Lift one or two Rhubarb roots into the greenhouse, where they can be forced. The roots should have a good ball of soil round them, when lifted. Replant in boxes of good soil, and stand them under the greenhouse stages.

Strawberries can be brought into the greenhouse for forcing.

Cinerarias and Primulas should stand near the glass where they can get plenty of light. This will hasten the blooms, to brighten the dull days of winter.

Christmas flowering bulbs need plenty of warmth and plenty of water.

Lilies-of-the-Valley can still be potted for forcing. Pot into pots or boxes in a leafy soil. Cover the crowns with coco-nut fibre; if this is not available, cover the crowns by inverting pots over them, until the leaves are about 3 in. high, when the cover can be removed.

Prepare composts for seed sowing, to save time later, when the rush begins.

Prepare boxes, wash pots, write labels, and make out seed orders for the earliest sowings.

03. September 2013 by admin
Categories: Kitchen Gardens, Uncategorized | Tags: , , , , , , , , | Comments Off on THE GARDENING YEAR UNDER GLASS


Get the Facebook Likebox Slider Pro for WordPress