Thompson & Morgan
Facebook Q&A Session 25th July 2014

Thompson & Morgan Facebook Q&A Session 25th July 2014
- Your horticultural questions answered.

Our horticultural expert Sue Sanderson runs a fortnightly question and answer session - so if there is something that has been eluding you in your garden, post your question on our facebook page and she will get back to you during her next Q&A session.

View the answers to our previous sessions.

  • Michael Chalmers
  • How do I encourage next year’s growth on your illumination pink foxgloves.

  • Sue - T&M Horticultural Expert
    Sue Sanderson - T & M Horticulturalist
  • Hi Michael. The best way to ensure a great display next year is to keep your plants in tip top condition. Water foxglove plants regularly during particularly hot periods. They will also appreciate the occasional feed of a balanced fertiliser this summer. Throughout the growing season you can deadhead any faded flowers to promote more flower production this summer.

    In autumn, cut back any remaining old flower stems to encourage plenty of new side shoots. Although Foxglove ‘Illumination Pink’ is hardy in mild parts of the UK, I would recommend that you move any that are in containers to a position with a minimum temperature of 0°C (32°F), and water sparingly during the winter months. Border-grown plants can be lifted in autumn and potted up for over-wintering. Better safe than sorry! I hope that helps.

  • Leeanne Ghent
  • How do you get rid of the horrible vine like weed please? It's driving me mental thanks.

  • Sue - T&M Horticultural Expert
    Sue Sanderson - T & M Horticulturalist
  • Hello Leeanne. I’m guessing that you are probably referring to Bindweed which is a rhizomatous perennial. The rhizomes (underground stems) spread deeply and in all directions. They can reproduce from just a small fragment of stem or rhizome which makes them difficult to get rid of. It’s a good idea to try and gently fork out as many rhizomes as you can before collecting them and disposing of them in household waste - don’t compost the pieces as they will quickly regrow all over your compost heap! They are easy to spot as the rhizomes are white.

    Any further growth can then be treated with a weed killer that contains glyphosate, which is carried through the plant to its roots, causing death of the entire plant. This is a non-selective chemical and will kill your garden plants too if you are not careful so make sure you cover the plants you want to keep before spraying! To get the best results spray the weeds on a still, overcast, dry day. If the Bindweed is growing among established borders then you may prefer to use this chemical in gel form. It can be painted directly on to the leaves of the weed, thereby minimising the risk of killing your surrounding plants by accident. In severe cases you may need to reapply the herbicide. I hope that helps Leeanne.

  • Fall Knight
  • Hi sue. I collect tomatoes seeds from tomatoes but when I grow the seed the next year, why are they not the same as the first?

  • Sue - T&M Horticultural Expert
    Sue Sanderson - T & M Horticulturalist
  • I suspect that you are saving seed from F1 Hybrid varieties but these will not come ‘true’ in the next generation. These tomato plants are produced from 2 parent plants both of ‘pure’ breeding lines, in order to create a hybrid with particular characteristics from those parents. When you grow plants in your garden they are cross pollinated by insects, thereby introducing different genes. In addition, F1 Hybrid will often revert back to the ‘type’ of the more dominant parent line and take on those characteristics.

    I know that this sounds rather complicated - it can take years to develop an F1 hybrid which is why the seed is so expensive compared to open pollinated varieties. You can read more about F1 Hybrids in this article. You would probably have a bit more luck if you stuck to non hybrid, open pollinated varieties - many of the Heritage Tomatoes fall into this category. I hope that all makes sense for you Fall.

  • Christine Colgrave
  • My mature, variegated Holly drops half it's leaves at this time of year. Any remedies, Sue?

  • Sue - T&M Horticultural Expert
    Sue Sanderson - T & M Horticulturalist
  • Hi Christine. Like most evergreens, Holly will drop its leaves when stressed in some way. Water stress would be the first thing that I would check for at this time of the year. You don’t mention any other symptoms but it would certainly be worth taking a look for any indications of pest infestation or disease. However Holly is generally quite a tough and resilient species, and a mature one will often ride out any pest or disease problems without the need for intervention.

    If the tree appears to be otherwise healthy then I would put this down to normal leaf drop. Even evergreens need to discard old leaves to make way for new ones. Provided that the shoots are green and healthy then you needn’t worry - fresh new leaves will be produced to replace those lost. Just watch out if you are walking about barefoot!

  • Susan Macmillan
  • Hi I have a agapanthus plant what's the best way of looking after it in winter and when the flowers die do I cut it back? Thank you

  • Sue - T&M Horticultural Expert
    Sue Sanderson - T & M Horticulturalist
  • Hi Susan. Agapanthus are really easy to care for. Leave faded agapanthus flower stems intact to enjoy their architectural seed heads during autumn. When the first frost blacken the seed heads, cut the stems back to ground level but leave the foliage to die back naturally. Protect plants from severe winter weather by providing a dry mulch of bark chips or straw in late autumn. Container grown plants can be moved to a frost free position over winter if you live in a particularly cold area, although I have always got away with leaving them outdoors next to a warm wall. Divide agapanthus clumps in spring when they become over crowded. I hope that helps.

  • Ruby Anne Mackenzie
  • Hi I have 3 buddleia buzz all in containers all treated the same and flowering well but the magenta one has lots of yellow leaves from bottom to half way up ? Thanx

  • Sue - T&M Horticultural Expert
    Sue Sanderson - T & M Horticulturalist
  • Hi Ruby Anne. It sounds as though your magenta Buddleja may be suffering from a magnesium deficiency. This is usually indicated by yellowing of the foliage which progresses from the oldest growth to the youngest. This is why you are seeing yellowing from the base of the plant upwards. Often deficiency problems can be easily rectified by repotting in fresh medium - use a soil based compost such as John Innes No.2. If the problem continues the you can also help your Buddleja recover by applying magnesium.