My tomato leaves dry up at the top. The other leaves are fine .Growing in a pot with Potting soil.
Thankyou for contacting Toronto Master Gardeners about your drying top tomato plant leaves. It looks as if they might also be yellowing a little? The good news is that the rest of the leaves are abundant and look healthy.
There are lots of diseases and pests that can affect tomatoes but from your photo , so far, these look unlikely. For example Fusarium wilt can make leaves look like yours but usually starts at the bottom of the plant and works its way up, yours is the opposite. Pests and diseases can make leaves look like yours but usually also display holes in leaves, spots, white powder, withering of the whole plant, webbing etc., none of which seem from the photo to be a problem here .
However, please remove the affected leaves immediately in case they do contain or attract a fungus, disease or pest. The abundant good foliage remaining will still allow for photosynthesis and fruit ripening .
Do keep as much good air circulation as possible and don’t water the plant from above so that the leaves get wet.
Let’s assume for now that your plant does not have a disease or pest but if this progresses or you rethink it , the Ontario government site http://www.omafra.gov.on.ca/IPM/english/tomatoes/identification-keys/disease_08a_02.html has very good information and a disease identification key which will lead you through a series of questions to help you identify your problem .
But for now, let’s look at other possibilities:
Could the leaves be sunburned? or windburned (you mention it is potted ..is this because you are on a windy balcony?) The photo doesn’t make it clear if all the top leaves are drying out or just some. If all, perhaps sunburn /windburn could be your issue.
Tomatoes are heavy feeders so let’s consider a nutrient deficiency. Even with good quality potting soil, by mid summer , many gardeners fertilize their pots ( you could try a 6-12-12 fertilizer or placing organic compost on the surface but the compost option would take longer to take effect . )
You are probably already watering consistently but only when the top 1 inch of soil is dry and doing so in the mornings. It has been very hot so perhaps it needs more water? Since your fruit looks fine, this is not likely your issue but do consider it as leaf problems can indicate either over or under watering.
The photo doesn’t show the size of your pot, but tomatoes need a lot of room and feeding. Root-bound plants are unhappy and water and nutrients run right through the soil.
I hope this is helpful and that you soon get to enjoy those gorgeous looking tomatoes .
You may find the following information from two of our archived posts to be of interest: