Hibiscus

I bought a lovely Hibiscus shrub 4 years ago but it never seems to be successful, only ever having 3 or 4 lovely pale mauve flowers and small leaves and not lots of them either.  It is sheltered from winter winds but in a sunny well drained spot.  I give it a good mulch each autumn with 2 year rotted horse manure mixed with home made compost.  I have never pruned it as it has only grown about 3ft tall.   Any suggestions would be appreciated

Hello Stephanie,

It sounds as though you've given your hibiscus a good spot and mulching and not pruning it is the right approach.

Have you ever tested your soil? Hardy hibiscus do not thrive in acid soil. If you want to know if you have acid soil you can buy soil testing kits from garden centres. Sometimes some parts of the garden are different from others so it's good to test all over. They also like moist (but free-drained) soil, so it's good to give them plenty of water in the summer.

Having said all that, my dad moved into a flat where there was a hibiscus that wasn't thriving at all. His soil is alkaline so it should have been OK. When we dug it out to remove it, we found it had been planted several inches too deep, so that gave us the answer!

Do let us know how your investigations go and good luck,

Emma

gardenersworld.com team

Thank you for your advice.  I have done a soil test and the ph is neutral at 7.  Should I be testing for other things like nitrogen , phosphorus or potassium ?.    I am determined to make this the year my Hibiscus shines !

my hibiscus is about 15yrs old( it's redheart) I prune it lightly after flowering as the ends of the stems look thin and shriveled, then as the new growth starts I cut back to a good bud, the same as you would for roses, I've fed  it with Gromore a few times, but I never see any differance from that, it always has loads of flowers and it grows in peat enriched soil because 40yrs ago it was heavy clay, It could be that it's still a bit young, I have fun growing more plants from the seed, but they hardly ever come back the same colour as the parent plant, but it's great fun waiting to see just what colour the flowers will be,

I am attempting to grow Hibiscus from seed for the first time this year. Not a very sophisticated approach - all purpose compost in a widow sillpot ensconced in a plastic bag, about 20 to a 6" pot. What germination rate could I realistically expect? I suppose the seedlings will need hardening off in a cold frame? No idea what the parent plant is like as seeds bought on e-bay but it's part of the thrill of the chase!  

I have a hibiscus which also has never produced flowers, it is covered with buds but every year the buds appear to be knawed away at before they manage to flower.

Have moved it from front of house to back and still the problem remains. Have tried spraying to kill off any infestations as soon as buds form but still after 5 years, the same problem - any suggestions as this year I feel is the last chance saloon for my plant?

Jan C

Hello hibiscus lovers,

A lack of flowering may be due to our recent lack of long hot summers. They always flower better after a good summer, so maybe we'll get lucky this year! However, Jan Chandler, your problem could be botrytis. This is a fungus that is always worse in cool and wet conditions. It can damage the flower buds, so that the flowers are spoiled and will never open. Unfortunately controlling it is very difficult, but improving the air-flow around the plant, by reducing crowding will help and so will removing all old plant debris from the site.

Emma

gardenersworld.com team

Thanks Emma, seem to have complied with all of your above suggestions, with planting and clearing site around the area, so will see if any luck this year with a hoped for hot summer for us all to enjoy.

Jan