Your Gardening queries - 16

"Bougainvillea is a plant that thrives on neglect. Give it lots of sun and let it dry out quite a lot between waterings (in containers). Protect it from cold and do NOT fertilize often. High nitrogen fertilizer will PREVENT blooms, not encourage them. Cut it back when it has finished flowering. It only blooms on new growth, so a good annual pruning will improve flowering the next year. It is not unusual for a Bougainvillea to droop or lose leaves in winter (and summer in some cases). It is a plant grown for it's colorful bloom, not foliage, so don't panic if plants look skimpy or bare at times. Give it sun and warmth and it will eventually bloom.
Finally, it is very important not to disturb the roots of Bougainvillea- especially in the case of young plants. When transplanting, do everything possible NOT to tease or disturb the rootball. Doing so can easily result in the death of the plant.
Bottom line is there are only three things that will kill a Bougainvillea - extreme cold, too much water, and root damage. Prevent those three things and your Bougainvillea will thrive."

A: Unfortunately there is not a lot you can do, apart from covering the plants with a layer of fine garden netting. I do this myself in the winter to stop the birds eating the Pyracantha berries.  

Q: Shirley tells me:- I have lost three clematis this year. They seem to come into growth and look healthy enough, but then I noticed they were covered in aphids. I sprayed them, and almost immediately they shrunk and turned black I have now cut them right back. Could you explain what happened. I have lots of clematis in my garden, some struggle but the others are fine. 

Could you also help with my honeysuckle which has yellowing leaves that are dropping. 

A: It sounds as if your Clematis plants have become the victims of `Clematis Wilt`.. I lost a perfectly healthy and established clematis last year and it was almost certainly due to this disease..  

If in the future you plant a new clematis, plant it deeper than the pot it comes in and the chances are it will survive despite the possibility of it succumbing to this disease. It gives new shoots a chance to form apparently.

Often honeysuckles drop some of their leaves in a spell of hot and dry weather. Try spraying the plant with a hosepipe set on fine mist and giving it a liquid feed.

Last year saw many honeysuckle problems for some reason. Many were as yours, with leaf drop and others had no flowers!

Q:  George wants some advice:- I have a very good show of Sweet Williams this year, the first time I have grown them for years. 

My problem is that they are all in full bloom together, so do I cut them in order to produce another flower, or once finished they will not reproduce? none of the books give the answer.

A:  Sweet Williams are biennials, sown one year to flower the next and then discarded. I tend to leave them in the ground until autumn and find they readily self-seed, thereby saving me the effort of sowing seeds.. Young plants produce the finest flowers, and it is advisable to raise a fresh stock every year.

If you cut off the dead flower heads they may be tempted to flower later in the year, but I doubt it would be worth the trouble as the flowers would probably be quite insignificant.

Q: Carol wants to know:- When is best time to put out monkey grass, also evergreen trees such as white pine or spruces (blue & green)?

A:- It is normal for a yukka to throw up numerous flower stems as it gets more established. You can cut them off after flowering and also remove the lower dead leaves to tidy up the plant. The yukka will grow new flowers next year from the top of the plant, or slightly to the side, and you might find that where the flower stalk was, the plant may then divide into two stems.. 

* Be very careful of your eyes on the sharp leaves, these plants are lethal. I used to cut the sharp pointed ends off when the children were smaller.