I think I killed my grosso lavender for good.

[mulderitsme]

It was in direct sun, in a fertilizer mix (Black Gold with "resilience"). At first I didn't water it too much, it did ok. I would water it at night and in the morning it would slightly wilt until the sun hit it. The direct sun was too much, so I put it in partial sun, which it seemed to love. I started to water it about everyday or every other day depending on how hot it is (it's been around105 degrees for the past few weeks). Then the upper stems permanently drooped and dried out, most of the blooms didn't open so I brought it inside. Nothing helped, it completely dried out, leaves, green stems, and all. I cut off all the dead and trimmed it down to the woody part--I think that's where I really fudged up--a lot of the woody part. I thought it would promote growth.
Will it ever grow back or did I murder one of my favorite plants?!
I was so excited to get my hands on some grosso. I have two other kinds, one from Walmart (I know, I know), and another from the local college's garden sale. Both of these only get partial sun and are doing terrifically. I've had all of them since about April. They are all in containers. The grosso was in terracotta while the other two were in plastic pots.

[imafan26]

Lavender does better out in well drained slightly alkaline soil and in full sun. Once established it does not need a lot of water and it does not like wet leaves so it is best not to water it at night. It becomes a large mounding plant and will grow knee high or better in the ground. It should be cut back but only cut back new wood. Once a year it needs to be pruned back to stimulate new growth or it gets on the leggy side. I usually do mine in January since it rains a lot then and the leaves will turn black anyway. I try to prune only half and wait to make new leaves are sprouting from the old branches before I cut off the rest. I have killed lavender by cutting it back too much into the old wood. Lavender resents fertilizer so fertilizer sparingly. I only use a small amount of slow release fertilizer once a year (nutricote). I have used terra cotta and plastic pots. Mine actually do better in terra cotta pots but I water everyday so I need the pots to dry fast. I also group my pots together, which increases humidity and insulates the inner pots from the sun. Sun heating up the pots will make the plants wilt in midday. If the pots are too hot to handle the roots are not happy either.

The lavendins are easier for me to grow in zone 12a than the augustifolias. The only other lavender that grows best in zones higher than zone 8 is lavender multifida which is a landcape lavender. Mulifeda is mustier and not really an edible lavender, but it blooms nearly year round and the blooms actually open. I mainly use it for its landscape value anyway. In my zone the austifolias are partial shade plants and the buds will not fully open and I have a hard time getting them past their first year. Most of the augustifolias and lavendins will only bloom for a short time in summer. Some of mine are blooming now.
Below are a couple of links I used that were helpful for me to select the right lavenders for my zone, and how to care for them.
P.S. Walmart lavenders and plants are fine. At any big box store ask what days they get their deliveries, that way you get the freshest selection. Some places bring in plants, seeds, bulbs from far away places. This is especially true of bulbs and trees. Make sure they will grow in your zone before you purchase.

https://sunshinelavenderfarm.com/planting-care/
https://www.mountainvalleygrowers.com/l ... ndtips.htm

[mulderitsme]

Thank you for your detailed reply and the links! I appreciate it very much. Now I can do a better job of caring for lavender. I think the fertilizer may have been what did it in :/ with a combination of it getting too dry too fast. This summer is crazy and indecisive. A few weeks ago one day it was about 88 and a few days later it was over 100. I think my plants don't mind it for the most part, but it's hard for ME to adjust to lol. Well, it's my first real garden and no better way to learn from experience, especially mistakes. I'll no what not to do now.

[applestar]

Black Gold all purpose is described as moisture retaining, and they also have spricifically moisture retaining formula that presumably retains moisture even more. Neither of which sounds very good for lavender.

Resilience looks like a a brand of potting mix with added Silicone. I'm guess they used it as an ingredient in their own blend?

...Which made me pause from saying "I think you should add more sand" ...but I usually add some sand -- maybe 1/3 to 2/3 cup to about 3 cups of premium (already well draining) potting mix.

While I have lavender in a pot, I also "mulch" with mostly sand blended with a bit of potting mix to prevent crusting. I put the pot on "risers" so it's NEVER sitting in water.

In the ground, I make a gravel.sand mix with added dolomitic lime where I plant lavender,mom plant in raised mounds.

[rainbowgardener]

All of the above. It wasn't the heat that did it in, lavender originates in very hot, dry climates and thrives on it, it was the water, fertilizing, water holding soil. And then once you cut down into the woody part you finished it off. Lavender does not regenerate from the woody base.

[imafan26]

I have clay soil but I amend it with cinders, you can use sand. I had a lavender plant (lavender multifida) in my front yard for a few years until it 42 days and nights of rain killed it. I planted it along my driveway that slopes toward the street. It had morning sun and lots of air since it was in a border planting strip. The house did shade it from the afternoon sun. I have a drip system there so the leaves did not get wet until it rained and I rarely fertilized it, when I did, I used osmocote or nutricote.

I am increasing my lavender collection again. Right now I have them in pots and I am trying to get rid of the bindweed and nutsedge in the front yard before I plant them out. I have the lavender in 4 inch pots (from cuttings I made), 1 gallon pots, and a provence in a 3 gallon pot. I have the pots under the patio eaves so when it rains the lavender will only get rain that is driven by the wind. Most of the rain will miss the lavender. I make my own mix so I have a 50/50 peat lite with perlite. I can add a teaspoon of dolomite lime, but I prefer to use a handful of vermicast compost in a 5 gallon bucket. Vermicast is the only compost I have not had probems with in pots and it is rich and alkaline so I don't need much.

I have multifida, Goodwin Creek, Provence, lavender dentata, Fred Boutin. I have tried hidcote and lady lavender but they are annuals here and the buds don't really open.

I did grow lavender from seed. It took almost 4 months to even see the sprouts. The snails got into the container and ate all the seedlings. Lavender roots easily from cuttings if you take them at the right time.

I would really like to get the white lavender, but no one has brought that one in. I don't think I want to try seeds again as snails are a chronic adversary for me.