Lynn Di­b­ley on how to help your house­plants stay in tip-top con­di­tion in win­ter

Re­duce wa­ter­ing and trim back ex­cess growth to keep them tip-top

Garden News (UK) - - News -

As most plants de­pend on sun­shine for en­ergy, they start to shut down in au­tumn to con­serve en­ergy dur­ing the darker win­ter months. Large plants which dur­ing the sum­mer months would have needed wa­ter­ing daily, now only need a light wa­ter­ing once a week or fort­nightly, de­pend­ing on the av­er­age tem­per­a­tures they’re grow­ing at.

Ever­green plants shed their older leaves dur­ing au­tumn, which is why you can end up with bare stems and only healthy young leaves clus­tered at the tips. This is es­pe­cially true with the taller-grow­ing cane be­go­nias, such as ‘Lit­tle Brother

Mont­gomery’ and ’Lucerna’, or the taller im­pa­tiens, such as Im­pa­tiens

ni­amni­a­men­sis. If left un­cut these plants will get taller year by year but they be­come un­gainly. It may seem dras­tic, but I like to cut back cane be­go­nias and im­pa­tiens in the au­tumn, ready for the young growth in spring. This young growth will come from the base of the plant and helps to cre­ate a denser and more com­pact, stronger plant.

When cut­ting a cane be­go­nia down in the au­tumn, po­si­tion the plant on a ta­ble or bench at waist height so you can stand back ev­ery few min­utes and check that the fi­nal shape is go­ing to be uni­form. With a multi-stemmed be­go­nia, af­ter re­mov­ing a few stems I’ll turn the plant be­fore re­mov­ing the next few stems and con­tinue cut­ting and turn­ing un­til I’m happy with the re­sult. ‘Lit­tle Brother Mont­gomery’ will have many young shoots at its base and it’s this young growth which I’m re­ly­ing on for next year’s new stems. Start by re­mov­ing the older bent or twisted canes and those that are elon­gated. ‘Lucerna’ gen­er­ally has fewer stems so it’s best to only re­move about a third of them, cut­ting the stem above a leaf which has a bud for a shoot in its axil. Be­go­nia suther­landii dies back for the win­ter. It’s na­tive to the moun­tain­ous wood­lands of South Africa and of­ten grows along­side wild Strep­to­car­pus gar­denii, on stream banks. Dur­ing the sum­mer months these two plants need the same care but in the au­tumn strep­to­car­pus keep their leaves while B. suther­landii will die off com­pletely above ground. As the days shorten, the stems of B. suther­landii grad­u­ally all drop off and you’ll be left with a tu­ber in the com­post; dur­ing this process stop wa­ter­ing. If you’re lucky the plant will have pro­duced lit­tle bul­bils in all the leaf ax­ils, which, if col­lected, can be sown next spring to pro­duce masses of new plants. Keep the tu­ber and bul­bils dry and frost free dur­ing the win­ter.

Achimenes (hot wa­ter plants) and koh­le­ria are also plants which die back com­pletely in the au­tumn and leave rhi­zomes in the com­post. These rhi­zomes are formed from the roots and are a wa­ter and food re­serve with the abil­ity to pro­duce new shoots when con­di­tions are favourable. Achimenes pro­duce short rhi­zomes, 1-4cm (⅜-1½in) in length, while koh­le­ria rhi­zomes can be up to 40cm (16in) in length. In spring break the koh­le­ria rhi­zome into 2½-4cm (1-1½in) sec­tions and use about seven pieces in a 12cm (5in) di­am­e­ter pot.

Plants which form a crown of leaves in a rosette shape of­ten dis­card their older outer leaves, strep­to­car­pus and saint­pau­lias (African vi­o­lets) are prime ex­am­ples of this type. Strep­to­car­pus leaves also draw their en­ergy away from the dis­tal ends (the old­est sec­tion) of leaf, form­ing a nar­row, yel­low, trans­verse line (ab­scis­sion line) across the leaf. The fur­thest sec­tion of leaf turns pale and will even­tu­ally drop off. You can has­ten the tidy up by re­mov­ing the sec­tion of leaf above the ab­scis­sion line as soon as it ap­pears. cac­tus) will need to be po­si­tioned out of cold draughts and kept to a care­ful wa­ter­ing regime where they never dry out ex­ces­sively, oth­er­wise ei­ther of these prob­lems can lead to flower buds drop­ping.

Cut back the long­est and any bent stems on cane be­go­nias

Be­go­nia ‘Lucerna’ doesn’t need such a se­vere trim

Ab­scis­sion lines in a strep­to­car­pus leaf

Be­go­nia suther­landii will die back to tu­bers

Keep cy­cla­men in good light and wa­ter spar­ingly

Af­ter a long grow­ing sea­son koh­le­ria pots can be com­pletely full of rhi­zomes

The growth on Im­pa­tiens ni­amni­a­men­sis

can be­come un­gainly if left unchecked

Keep your Christ­mas cac­tus out of cold draughts

Newspapers in English

Newspapers from UK

© PressReader. All rights reserved.