Q: Hello.  Please could you give me advice as to how to eradicate Red Ants from our rather large lawn.  They are everywhere.  Ruining the grass.  Also, please could you advise me what I am not doing regarding my celeriac growing.  A few years ago I grew some magnificent Celeriac from seed.  I have tried year on year since then but end up with marvellous tops of the celeriac, but very disappointing roots, in fact, tiny.  Not useable.  Your tips and advice would be appreciated.  Thank you, Jane Winmill

A:  I would suggest that the best product is Ant Stop. There is a feeding station which you can buy which placed by the ant hill works very well. However, I personally prefer to disturb the ants and spray them with the ready to use version of Ant Stop. This does not kill on contact, but as the ants have hairs on their legs when they return to the nest and clean each other they therefore ingest the poison. You will need several applications.   As for the celeriac I am concerned that you are maybe using the same ground to grow them. You would be better to change sites. Have you added organic material at any time to the area? If so, it is better to use the plot for growing on the following year. The other problem that you are describing is usually created by fluctuations in water levels and temperature. If the plants dry out and then is watered you will achieve top growth rather than bottom growth.  Hope this season year are more successful.

Q: I have a Cornice pear which I believe has scab on some of the fruit with a few black marks on a few leaves.  It is a Minarette and about 20 years old.  The fruit is perfectly alright to eat, but it looks rather unsightly!  Is there a spray or something to add to the soil please?

A: The pear does indeed have pear scab, and sadly there are no sprays for this available as all have been taken off the market.  Cleanliness is the most important thing, so clear up leaves and dispose of them rather than placing them on the compost heap.

Q: I have a Hypericum shrub which has grown to about 5-6 feet high.  I will either have to remove it or reduce the height and width.  When is the best time please?

A: The Hypericum sounds superb, but would be best cut back hard in spring, and can be cut back really hard.

Q:  Last year we moved our olive tree by about a metre as we had landscaped our garden. We moved it around last April, the weather did get cold over this period. The leaves fell off and nothing has grown back since. If you scrape the bark it is still green underneath. I was going to cut it back once the risk of frost has passed. Is there anything else that you would recommend to bring the tree back to health or will it just die?

A: If its green underneath it still has a chance of living. I therefore suggest that you leave in it situ and do not cut it back anymore.