Nine years ago I wrote about the coloured leaves of this houseplant. Now I have got interested in oil painting and this plant makes a dream of a subject for this week. This is what was published at the time and I recommend a later more detailed post. Read also about Croton the other name for Codiaeum,and related houseplants
‘You do not need flowers to produce colour in your houseplants. In addition to Begonia Rex and its relatives why not try growing some Codiaeum, an easy to maintain leafy plant.
Codiaeums are interesting foliage house plants also called Joseph’s Coat.
Codiaeum Cultivation Tips
This variety is called ‘Petra’ but you may also find ‘Eugene Drapps’ with long lance shaped leaves almost entirely yellow.
Keep plants moist and in good light with a temperature of at least 60-70Â° F.
Root 6 inch cuttings taken from the top of the plant at 70Â° with a bit of bottom heat.
Plants can be encouraged to branch by pinching out the growing tip.
Frequent feeding is needed except in winter when growth slows.
Large plants will have lots of roots so it may be worth potting up a size using loam based compost.
Red spider mite can be a problem with Codiaeums
Without good light but not full scorching sun the colouring will not be as strong and bottom leaves may be shed.’
During spring the space in your greenhouse is at a premium. We all have our own ways of using the opportunities and here are some of my ideas and Yorkshire experiences.
My glasshouse is the standard aluminium roof-span type. I aspire to a dutch type with sloping sides and bigger panes but they restrict tall plants near the glass. I’m too traditional to opt for an octagonal or dome shape and they rely on shelving for more space.
My past attempts with mini greenhouses and plastic constructions have been frustrating and are usually abandoned.
I have just got around to placing concrete flags under the staging – previously it was bare soil but seldom used for growing. Now I store dry goods that are regularly needed and small gizzmos and fixers. Now I don’t need to resort to the hut or garage every time I need something (time is as valuable as space).
The central path has long been flagged for 80% of the length so the growing area is ‘U’ shaped.
I use all internal central path for pots and trays on an interim basis. I also have some flags outside the door for moving plants out for short periods and hardening off.
I have a permanent wooden stage the length of one side and a temporary, portable aluminium stage that fit across the far end.
My aluminium frames have a central channel where a moveable support can be fixed for bubble wrap screening or light string support. I also string from the roof for tomatoes.
Wires or washing line is strung across some areas affixed to the frame to support growing plants. Pegs are used for several purposes.
Maximising Crops my way
My favourite flowering crops are auriculas and cyclamen that are ready to go outside before other plants need the space.
If I prick out too many plants into pots I need to ration myself as space becomes tight for a couple of weeks
I have had good results growing first earlies in potato sacks as long as I protect from hard frost and earth up by topping up the bag. They go outside when I need the space as the frost is virtually done.
Once seedlings are planted out I grow tumbler tomatoes in pots on the top of the bench and previously a courgette or two under the bench but they eventually gets in the way.
I grow tomatoes using a type of ring culture augmented by a hydroponic trough of nutrient and some wicking see below
Chrysanthemum follow tomatoes started off in front of the trough
Catch crops of lettuce and other salads get stuck in where I can.
Through winter I raise pots of early bulbs particularly hyacinths
Other Greenhouse Observations
The foundations are 99% perfect but I would strive for perfection if starting again. I would also build a ramp up to the threshold.
The only growth nearby is a plum tree on the north side but there is no overhang and the light is good.
I need to shade it with cool-glass paint as the sun gets stronger. A tip is to paint the shading on the inside, it is easier to reach and wash off. Outside the coolglass tends to adhere to mucky glass .
I never invested in blinds or shades. I also use scrim, muslin or horticultural fleece as a temporary covering if needed.
I use small flags to retain deeper soil where I want it. (see front right)
We gardeners hopefully learn as we go along and this post is an update of a 6 year old report on indoor primulas.
‘Indoor plants that are in full flower in January include the strongly coloured Primula Obconica shown above. They look good in traditional blues, pinks and white with the new Twilly series including a strong red. There are plenty of long lasting blooms particularly if you pick off dead flowers. The hairs on the back of leaves can be an irritant so take care if you have sensitive skin, the plant is also known as Poison Primrose.
Plants at garden centers may have been grown specifically for a quick show of colour that makes them saleable and decorative as indoor plants. They are probably not frost free or very hardy.
Unlike other Primula obconica varieties, Twilly Touch Me is primine free, so causes no skin irritation.
Grown from seed give them dark to germinate. They flower the following spring/summer in the cool greenhouse or as a houseplant.
Primula obconica produce a dozen different colours of flowers.
The flowers last for several weeks if spent flowers are deadheaded regularly.
Do not let the plants dry out and the leaves become floppy.
Other species of Indoor Primulas include Primula malacoides a perennial plant for a heated greenhouse or conservatory. Also known as the Fairy primrose it is NOT hardy.
Primula sinensis the Chinese Primrose aka Primula praenitens is hard to obtain but the flowers look stunning so it is worth looking for.
Showing the soft fleshy leaves of ‘Twill Touch Me Series’ of Indoor Primula obconica. The Primula stem holds the flowers proud of the leaves.’
I have flirted with geraniums for several decades but never achieved the full satisfaction of a great display. Now I have a new plan to dedicate an area in the garden, dare I call it a zone? to some of these colourful plants. To give me an incentive to dedicate time and effort I have given it a name Pelargonia as I thought Geraniumistan was going to confuse the issue with cranesbill geranium or hardy geraniums.
As you can see from the search link I have blogged on 67 occasions about pelargoniums and geraniums over the Gardeners Tips years.
Frost Tender Pelargoniums
After several good years I got careless one weekend and lost some good growth and suffered several set backs after an air frost. A similar event took place 6 years ago and that was at the beginning of June.
Remember if your pelargonium stems get frosted then the plant will die and not recover!
In the North of England there can be frosts late in May and early June. In Scotland and on high ground keep your thermometer handy whenever frost is threatened.
Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â My flikr selection -hover & press the arrow
Zonal geraniums are more accurately called ‘Pelargoniums’. The zonal is named for the distinct bands of colour around the leaf. On the example below 3 distinct shades are obvious even in a black and white image. These distinctive colours and patterns are quite sought after and some varieties are grown for the leaf shade alone.
Pelargonium House Plants
If you are worried about frost, geraniums make fine house plants. They can be kept in flower throughout the year and the flowers can be picked for a small vase. If you time it right when several ‘pips’ are showing full colour they can last a couple of weeks as the other pips keep opening.
Regular weekly feeding of high potash feed with an occasional nitrogen booster will grow a substantial specimen.
Pinch out the growing tip in April and June to get bushy plants with more flowers.
Can you grow too much of a good thing? Yes I think so. There are only so many plants you can accommodate in the garden, house or even through life. So as part of enjoying the growing aspect of gardening I have started to deliberately grow for giving plants away in this case Gloxinia.
Selecting the Gift
A plant in flower is far more attractive than one the recipient has to grow-on or wait to see how it looks.
A plant that still has lots of buds to open or develop will extend the pleasure. (See the latent buds on the next photo).
Presenting the present in an appropriate way is worth a bit of effort. I have been buying a range of bowls and plant pot holders from charity shops to act as containers. In many cases I can colour co-ordinate to match container and plant. Artistically minded may want to add a label or bespoke wrapping.
Not everyone believes the Gloxinia I am giving are houseplants so I should consider providing a bit more information.
Simple Advice For Gifted Gloxinia
Gloxinia like plenty of bright light without direct burning sun.
Turn the pot round so the plant and flowers develop evenly. They love to bend towards the light.
Water from the bottom when the compost is dry and the leaves are floppy. Err on the side of too little rather than too much water.
After flowering which may last 6-8 weeks, allow the plant to rest and die back.
Keep the dry tuber until next spring if you want to try to regrow your gift.
Tips on Growing Gloxinia
Tubers or corms may be found under the name Sinningia speciosa or Gloxinia and are part of the Gesneriaceae family that includes African Violets. They have been grown as florists gloxinia since being discovered in Brazil in 1815.
Plant shallowly in good compost with the buds facing upwards, this is usually the concave side like begonias.
Water the compost with warm water from the bottom to stop the tuber rotting and keep the atmosphere humid without getting the leaves or flowers wet or they will be stained with brown blotches.
Â If the furry leaves elongate it is a sign they need more light.
Do not expose to direct mid-day sun as the leaves are liable to become scorched.
GloxiniaÂ like a temperature above 60Âº when in growth.
Plastic pots are fine but I add some grit or perlite to help avoid water logging.
Â Schefflera arboricola, known as the â€œdwarf umbrella tree,â€ has small green leaflets attached to stout petioles. Indoors it will have a mature height of 3 to 4 feet.
Schefflera areboldÂ make good individual plants as indoor specimens in large decorative containers. The palmate leaves have 5 to 9 finger leaves from a central stalk.
Schefflera actinophylla can grow to heights of 8 to 10 feet inside and up to 40 feet outside in very warm climates. As well as being called the ‘octopus plant’ it also shares the common name of umbrella plant. For a 4th name it is sometimes botanically named Brassiaia actinophylla.
Where to Grow Schefflera Indoor Umbrellas
To keep the umbrella tree happy reasonable warmth of 15-20 degrees C is best.
Through winter the temperature should be at least 10-13 degrees C
A lightly shaded location is best. Bi-coloured leaves look best with some sun.
Avoid very sunny or dark locations.
Use a robust potting mix containing some loam to feed the plant for a number of years. Fertilise in summer during growth.
Cool, dampish conditions ensure happy cyclamen plants from now until Christmas. Do not let them dry out in your centrally heated house. Nor should you put them in draft
Indoor Cyclamen persicum can provide a splash of colour when all else is white and drab. I bought two for a pound after Christmas and chose this one because the flowers had not started opening. The tightly twisted buds are now revealing a mottled petal with an interesting cerise colouring.
The other plant I have drowned with too much TLC but its flowers were already a bit blown. This Cyclamen is on gravel in the pot and I am taking greater care. When it finishes flowering I hope to grow the corm on then allow it to dry out in summer. It will be saved in the pot laid sideways and brought back into growth next winter.
Dendrobiums like their roots confined in small pots. for good drainage use bark, perlag and charcoal to make up an open mix which drains easily.
Repot when either the compost becomes acid and soggy or when the pot is full of roots.
Plants from the mountains of New Guinea like a little moss mixed with the bark or they can be grown on slabs of bark or tree fern on a mossy bed. Such slabs need daily misting for most of the year.
Over enthusiastic flowering of small dendrobiums can lead to a premature death.
Small dendrobiums sometimes benefit from a steady gentle air flow.
In winter temperatures can drop to 40Â°C when you should not water or feed but give plenty of light and air movement. Buds develop in spring and new growths appear. Water sparingly until the new shoots have grown good roots then feed weekly during maximum growth.
Free draining potting mixes should always be used containing coarse bark perlite, sphagnum moss and even small pebbles if a little weight is needed.
Propagation is by division of the larger clump when it has filled the pot. Some Dendrobiums produce offsets. Generally they do not like any root disturbance.
Australian species and hybrids include the ‘Rock Lily’ flowers last only 3-4 weeks but Dendrobium bigibbum is often grow for cut flowers.
Dendrobium like plenty of bright filtered sunlight but avoid direct sunlight that may scorch the leaves. They can be difficult to re-flower if they do not receive sufficient light.
Never allow plants to stand in water as it may rot the roots.
Moss loving species can be grouped as either Himalayan, Australian or New Guinea (including Singapore). They can be grown on chunks of bark or tree fern on a mossy bed.
Prior to collecting material get your gardener to spray an insecticide to prevent pollen beetle and other insects being imported.
All flowers will last longer if a foxglove is included in the arrangement. If they are not desired or available make a tea by pouring boiling water on foxglove leaves. When cool use the liquid with water.
For delphiniums and larkspur add sugar don’t bother with the old Wive’s idea of an old penny (give it to the gardener).
For daffodils and narcissus add charcoal or camphor to the water and preferably keep them from other flowers.
Topmost buds should be nipped from gladioli, snapdragons and delphiniums.
Heathers without water will last for weeks in the house without withering or dropping needles.
Many spring flowering shrubs will last longer if picked in bud rather than full flower and stood in hot water first. Try this with Forsythis, Wintersweet, Witch hazel and willows.
If flowering shrubs must be used the whole shoot should be taken down to two buds above old wood.
Leave enough leaf material for plants to regenerate.
Old flowers may be about to set seed and will not last long in the arrangement.