Wilting Lilac

[G Burton]

I live in zone 14. I have a lilac that has a lot of sentimental value to me, but I can't seem to make it healthy. I'm thinking that I'm either over-watering or under-watering, but I don't know which. Here is what I see:

I'm getting satisfactory growth in height (it's now about 6 ft high now), but the leaves are curling inward, getting brittle, losing their green color, and getting some brownish spots. Leaves near the ground on the younger branches are doing fairly well. Some of the canes were so badly damaged last year that they did not leaf out this year. The lilac bloomed for the first time this spring, but I only got two flowers, and they didn't last long

Last year, my symptoms were similar. I concluded that I was under-watering. I was giving it a little over 2 gallons per week, and I increased the dose to 3 gallons per week. Now I increased it again to about 4 gallons per week

[Travis]

Please stop posting in HTML.

Knowing where you are would help.

Lilacs do best in full sun.

After the first or second year they usually require no supplemental watering. They do not require fertilizer. They like an alkaline soil. They do best in parts of the country that have a winter.

[G Burton]

[mleblanca]

Hello Loudette Zone 14 should have enough winter for your lilac to bloom. Since you (and I) are in an area of no summer rainfall and a very hot summer, lilacs do need watering. You didn't say how old the plant is, but 4 gallons is not much water for a 6 foot shrub, when the temperatures are hitting 100. That is only 4 gallon milk jugs of water! Barely wets the surface.......... Give your lilac deep watering until you can dig down at least 6 inches and still have damp soil. I am watering mine twice a week in this heat, and once a week when it gets below 90. Are you watering far enough out from the trunk? If you're using drip, it usually doesn't spread far enough into the root zone.

Stop fertilizing it until it becomes a healthy plant. Fertilizer is not Medicine for a sickly plant. ( You wouldn't feed a sick person a 12 course roast beef dinnner. :>) )I never fertilize my lilac.

The brown spotting could be a leaf spot fungus Everything seems to have it after the long, cool, rainy spring. The heat is helping some.

Do you use a mulch around the roots? That can really help retain moisture and keep the roots cool.

Are you pruning it ? If so, when? It should be pruned in early spring, soon after blooming. I would remove the lower sucker growth.. It's taking energy from the upper branches.

Another thought: soil. Are you in the clay soil belt near Sacramento? Lilacs like to be in a good drainage situation. The pH should be OK. We are mostly neutral around here.

Good Luck with your sentimental plant!

Emilie NorCal

[Travis]

That would be Sunset zone 14.

If all the other conditions I mentioned are present Lilacs should do well where you are.

[G Burton]

Thank you very much! That is very helpful.

[G Burton]

[G Burton]

I need to correct some of the information in my posting. I may have misled you, and I need your help.

I measured the lilac, and recalculated the water supply.

It is about 4 1/2 feet high. Yes, it is on a drip system. I am actually giving it 7.5 gallons/wk. I water it twice per week at 3.75 gallons each watering. The water was being dripped right at the base of the plant, and I am taking your suggestion to hook it up so that the drip is all around the bush and about a foot from the trunk. I dug down, and there was some moisture 6" deep, but not much. It was mostly dry.

I'm in Fairfield, so you know my climate. As you know, it has been very hot lately and that may be a good part of the problem. The soil is mostly clay, but the lilac is planted in topsoil Below that, I'm sure is clay.

Thanks to you, I have stopped fertilizing and I am determined to save this plant if there is any way I can. Can you now tell my if I'm overwatering or underwatering?