Wednesday, April 8, 2009

Gardening: The Bolt

Isn't this just lovely? 

Gardening is full of surprises. This flower is what you get if you let arugula go nuts, or bolt. Dr. Punger at Permission to Mother asked me for more information on bolting plants the last time I did a garden update and I thought other people might be interested as well. 

I looked in all my general gardening information books and was surprised to see only two mentions of bolting and no really good explanation. Basically, bolting is gardener lingo for explaining that certain plants are going to flower and seed. This term is reserved for those plants which we grow primarily for the leaves and not the fruit or seeds. So tomatoes don't bolt, they "flower" and "set fruit" - happy, complementary terms. Lettuces, dark leafy greens, and herbs bolt - a harsh, bitter term. For these plants we endeavor to put off their going to seed as long as possible for our benefit.  

I seeded several square feet with mixed lettuce seed (meant to be eaten young) but I got one solitary plant out of it (damn Japanese beetle grubs). It actually took quite some time to bolt, and here it is, just prior to actually flowering. Most greens get pretty bitter once they start to bolt, becoming much less appetizing. 

Cilantro is a notorious bolter. 

There are a number of factors that cause a plant to bolt, but they all come down to stress. Most leafy greens are cool-weather plants and bolt when it gets too warm for their liking. You can get around this to a point in a couple of ways. Look for bolt-resistant varieties (some of these are hybrids, which you may want to keep in mind if you avoid them as I do), keep the plants well watered (but don't drown them!), and try planting in a shady area or on the north side of a building if you want to grow them during warmer months. If you have the space I imagine you could also grow them inside, like in a basement, with grow lights if you really want mid-summer homegrown lettuce in a hot climate. Some greens do not transplant well and the shock of transplanting can also cause them to bolt. This is true of cilantro, which is easy enough to start from seed. If you really want a continuous supply of cilantro you may want to consider succession planting, or starting a new set of seeds every two or three weeks, so that you always have fresh cilantro. 

Remember that mysterious giant plant with yellow flowers? Well I think I determined it was kale, although not a kale I recognize. I ripped it out in a fit last week and look at the size of the thing. I am 5'3 and it was bigger than me (and heavy!). Amazing.

One more picture of the arugula. It is just so pretty.


Denise Punger MD IBCLC said...

Arugula does make a beautiful flower! It's hard to imagine that it is stressed. Thank you for all this information. I gleaned a lot of useful information. Now I know to move my plants to a shady area.

Hannah said...

Wow, your garden is so impressive! Mine rarely grows anything, let alone what I actually plant..!

Bethany said...

the arugula flower is really pretty. same for cilantro.

I love freaky mystery plants. once we had a 6 foot nettle. they grow really huge in WA. and just as unpleasantly picky.

I took an organic gardening class and they suggested making a leaning trellis for growing sun loving climbers and then growing lettuce under the trellis. I'm hoping I have the yard in shape for a real garden next year. This year I still have lots of work to do, but hope I can get the herb garden and fruit trees done.

Kimberly said...

Did you know the arugula flowers are edible? Let nothing go to waste!

Anonymous said...

Great hints thanks. I have trouble stopping my parsley from bolting. NOw I know my problem: I've only been growing it in full sun. I'll try growing it in a few different places around the garden.

Whatta said...

arugula flowers are quite tasty. they are peppery much like the leaf itself.

one hint...pinch off the bolting stems as they rise above the rest to coax a little more time for harvest. i do this on my lettuces and various greens.

cilantro seeds are AKA coriander, and the green seeds are quite prized by cooks. so, let cilantro bolt and harvest the seeds for cooking.

harvest the other seeds for planting next season.

Lily Girl said...

PtM - I'm glad you found this helpful!

Hannah - you can try having your soil tested if you think that is the issue. It can tell you if it is deficient in an important nutrient and you can amend the soil accordingly.

Bethany - thats a great idea. Companion planting can really increase your usable planting space.

LEF - I am in SoCal so I can grow my herbs and cool weather greens in full sun from late fall - early spring, but if I want them in summer I definately have to protect them as much as possible. Experimenting is half the fun of gardening!

Kimberly - that didn't even occur to me, but obviously makes sense! I'll remember that for next time.

Watta - thanks for the tips! I do pinch off the bolt stem on my greens as soon as I see them. It does extend the harvest time quite a bit. My cilantro seeds are starting to dry, I've already harvested the first few. The dried coriander is why I let it bolt - yum!