Plant Diseases/What's Going on With my Lavender???
QUESTION: Hi Melissa,
Can you tell me what disease my lavender is having by looking at the photos? I seems that the new young leaves are turning grey. I have tried cutting the dead new young leaves and tried spraying copper fungicide on it, however the problem still persist.
Looking forward for your reply, Thank you.
ANSWER: Dear Anthony, I'm sorry it's taken me so long to get back with you. I looked at your lavender leaves, and they are extremely troublesome, especially since you said you have been trimming off the dead wilted leaves and have sprayed it with fungicide. There are only two likely problems with your lavender. One is that you have kept the plant too wet and not permitted it to dry between waterings, and/or after watering you keep the plant with a saucer underneath that collects water. Lavenders hate to have wet feet (roots) and over saturated soils will kill them. The second possible problem is similar and is related to the watering issue. You may have a disease known as Phytophthora. This is a deadly fungal infection that is really incurable. It often shows up in plants with wet soils or in infected greenhouse plants. If this is your only plant, and you have been watering it too much, then slow down the watering, make sure to empty the tray completely after the water drains off, and see if it improves. However, if you have a lot of plants, and this is a new addition, I would discard the plant before it potentially infects any others. I have worked in nurseries that received plants infected with Phytophthora, and the owners tried unsuccessfully to prune or discard any plants severely infected and save the rest, but it did not work, and eventually all the plants in that group had to be destroyed. Make sure the lavender has as much light as possible, keep it dry, and if it doesn't look any better in a few more days, or looks significantly worse, throw the plant away. I wish I could be more helpful and guide you to a solution that saves the plant, but sometimes that isn't an option. I hope this information helps. Please write back if you have more questions, and I will answer more promptly. Good luck, Melissa
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QUESTION: Hi Melissa,
Thanks for getting back to me, I am really grateful about it.
By the way for your information I am situated in Pekanbaru a city in Riau province of Indonesia. We have a tropical rain-forest climate here with average highest temperature of 30C and an average lowest temperature of 23C. We have summer all year round and we only have wet and dry season throughout the year. Humidity level is high here with around the range of 60% to 98%. I am in low lying area, therefore it is extremely hot here.
Planting lavender may be a challenge here, but don't know for some reason I just want to keep on trying.
After seeing your answer, maybe my next step will be to place them in an open space but with partial shade as I have tried exposing the lavender to full sun and immediately most of the leaves at the top turn brown. hope it will get better after this steps.
And one more thing, My potting mix for my lavender is alluvial soil, building sand, compost, and pebbles with a ratio of 1:1:1:1. do you think this soil mix is still too saturated? should I increase the building sand to make it less saturated?
Picture attached are my lavender that I planted, as you can see, I am actually trying to figure a way to grow Lavender in my climate.
I thank you once again.
Read more: http://davesgarden.com/community/forums/t/1038883/#ixzz3ZHM2MNaS
ANSWER: Dear Anthony, I think it's wonderful that you are trying to grow something that might be a challenge. I love lavender and it's well worth the effort. You might want to increase the sand in your planting mixture, but you might want to rinse it before using if it has much saltiness in it. I also think you're on the right track putting them in an open space with some shade rather than in full sun. In your location, as close as you are to the equator, it may be too much for them to be in full sun. Try them at about 2 hours of sun a day and that might be enough. I wish you much success. Good luck, Melissa
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QUESTION: Hi Melissa,
You mentioned that you work in nurseries, is it a lavender nurseries? if it is a lavender nursery, May I know the how do they determine what fertilizer to use, how much fertilizer to use or how often do they fertilize their plant?
Dear Anthony, In the nurseries, lavender was mostly grown for sale and many homes have a lavender plant or two. I don't know if you can get Osmocote - which is the brand that we mostly used here in the US, but it is a time released fertilizer that was applied two or three times a year by putting a scoop of fertilizer on top of the soil and watering. Time released is good because it won't burn the plant. The fertilizer generally had a higher middle number, such as 5-10-5 or something like that. I think that if you keep it in a bright area but out of the long hot sun hours, and if you remember to not keep the roots overly wet, then you have a good chance for success. Good luck, Melissa