Monday, April 14, 2008

Common Lilac as Phenological Indicator

In Creative Homeowner's Gardening For All Seasons, it states that the "Common lilac is a good phenological indicator".


"Phenological indicators are natural timekeepers" supposedly better at telling us when to plant rather than going by the calendar or last frost dates.

It states, "Because weather conditions vary from year to year, timing some of your plantings by the development of lilacs in your neighborhood can be a more reliable guide than mere calendar dates."

"When lilacs begin to leaf out, (that is, when the widest part of the leaves grows out past the bud scales that had enclosed the leaf), it is safe to plant hardy annuals such as sweet alyssum, pansies, and calendulas. And when the lilacs are in full bloom it's time to plant tender annuals, such as impatiens and marigolds, as well as summer bulbs such as dahlias, gladiolas and tuberous begonias."

Considering we have a freeze warning again tonight and my lilacs already have significant bud formation, I wonder if this is truly a reliable indicator of when to plant tender annuals. I sure hope so, because I have a lot of plants inside that are getting huge and desperately need to go into the flower beds. A few plants have wilted and dropped over dead, I've probably over-watered and caused damping off disease. I also have an infestation of aphids, white flies and gnats on my indoor seedlings. I am so ready to move these plants outdoors!

I was wondering what you thought. Do you think this is a reliable method for determining when to plant tender annuals?

14 comments:

Sherry at the Zoo said...

Wow...I hadn't heard that before. I know my lilacs are barely budding. It's my favorite smell though and I eagerly look forward to it each spring.

I usually go by the frost free date of around May 15th. If I'm really feeling brave I'll start around the 1st of May if the 10day outlook is frost-free. This year, I bet that I'm not planting anything in early May. BRrrrr...It's cold out there today!

I didn't realize that you homeschool as well. Maybe I'll run into you at convention.

Frances, said...

Hi Robin, I am way behind on reading posts, but this one really caught my attention, as the lilacs are in full bloom here today and we are in a severe frost warning! I have read that it is time to plant beans when the lilacs bloom, that is way off base this year, the ground is still too cool, the seeds will rot. My seedlings have gnats and aphids also, probably from being outside for the few warm days and nights, then brought back inside for another week with the recent cold, windy spell. Those ants don't wasts any time farming their favorite treat, the aphid honeydew. Yuck. I hope to plant some of the babies out next week.

Robin's Nesting Place said...

Sherry, I've been homeschooling for about 12 years now. We love it and it has been great for our family. Wow, if I have to wait another month to plant my stuff outside, I'm in trouble! I think I'll take my chances, I'd rather have them die outside than inside. I may just have to cover them every night with sheets until it warms up. I won't start them so early next year.

Frances, I'm having to catch up on blog reading too. It doesn't take long to fall behind. My plants haven't been outside yet, so I'm not sure how the aphids got started. I didn't have them last year.

Jan said...

Robin, there is occasionally that late spring freeze, so I don't think I would always go by how leafed out the lilacs are. A frost free date is more reliable, but I tend to kind of push it if there has been warm weather earlier than that date. This year seems different than most weather-wise. Down here there is even a frost warning for tonight, which could set a new record.

Jan Always Growing

beckie said...

Robin, even lilacs get caught off guard by a freeze.(Like last year!) So, I wouldn't trust that advice. On the other hand, if your plants are suffering from indooritis, go ahead and plant them. With a sheet on cod nights, I'm sure they will be fine. We gardeners have a lot to worry about don't we?!

Lisa at Greenbow said...

We are to get that freeze tonight too Robin. It just doesn't seem right. I hope our pansies don't get frozen. I don't have much else out.

I had never heard your 'indicator' before. It would probably be correct most years.

Connie said...

I don't think I would trust this advice....our lilacs sometimes bud out during a warm spell in winter!

walk2write said...

I wonder what the global warming proponents would think about this phenological phenomenon. It's an interesting concept to be sure. Hooray for homeschoolers! We homeschooled our daughter for a few years in the St. Louis, Missouri, area. When we moved to southern Illinois in 1992, we could not find a good support group, and her interest (and mine) waned. Nevertheless, we all enjoyed the time we had learning together.

Anna said...

I want to know if cinnamon sprinkled on the soil of plants gets rid of gnats. Give a go would you? Then let me know! I had heard that about the lilacs and even though were are ahead of you down here. I haven't seen any in bloom down here. Our weather is suppose to be in the low 30s tonight. yuck.

Viooltje said...

What an interesting post, I didn't know that. My lilacs are all in bloom, and have filled the yard with their beautiful scent. And the weather is so...makes you forget of any frost danger. I hope no frost damages any of our gardens this year. And for sure what you wrote about lilacs must make sense. Or it did make sense, but nowadays, you just can't be sure of anything anymore. The weather's gone all weird and it's 'nothing' but Earth's way of showing us just how much a man has harmed this lovely planet.

Annie in Austin said...

I left my lilacs behind in Illinois but my gardening son lets me know what goes on there ;-]

We'd both heard about using the lilacs blooms... there's also used to be some saying about planting corn & beans when the oak leaves were the size of a squirrels ear.
I think there were either two or three years with frozen lilacs out of the last 35.

Annie at the Transplantable Rose

Robin's Nesting Place said...

Jan, I had issues with the last frost date last year. Indy has several depending on the source. Is so hard to wait when the weather warms up.

Beckie, I think I'll put them out tomorrow and start hardening them off.

Lisa, I checked and it didn't look like anything here was harmed by the freeze.

Connie, it seems like it would also depend on the location. Mine get full sun so they might bloom a little early than those getting less sun.

walk2write, we had a great support group in Alabama. Haven't really found a great group here. Although they do have great sports teams that my son enjoys.

Anna, thanks for the tip, I'll have to try it.

Viooltje, the weather certainly can be weird. I've done posts on all of the extreme weather we've had.

Annie, according to your comment then, it may not be fool proof, but a pretty reliable method. I'd say that is a very good record, and worth using the method.

The Gardeness said...

I've also heard this, specifically in relation to planting your peas. But with temps still dipping, I'm also wondering if lilacs can be confused?? Ours his leafed out and ready to go!

Anna said...

How long are you going to stay out there watching that nest? We miss you?