Is it too late to start corn in zone 5?

We started our garden late and I'm doing some of the veggies from seeds. Could I plant corn now, or did I miss the window?

Well, I just did a quick search and came across this website ...

http://www.ehow.com/info_8085919_planting-dates-zones.html

According to it ..

Zones 5 and 6

• 
  
  
  March -- April: Broccoli, carrot, collard, onion, peas
  
  March -- May: Turnip
  
  April: Asparagus, bean (bush), beet, cabbage, potato (Irish), spinach
  
  April -- May: Lettuce
  
  May: Beans (pole), lima bean, cantaloupe, cucumber, peppers, squash, tomato, watermelon
  
  May -- June: Potato (sweet)
  
  May -- July: Corn
  
  July -- August: Bean (bush)
  
  August -- September: Beet, mustard, spinach, turnip
  
  September (early): Lettuce
  
  September (late): Broccoli, cabbage, carrot
  
  September -- December: Onion
  

Read more: Planting Dates for Zones | eHow.com http://www.ehow.com/info_8085919_planting-dates-zones.html#ixzz1zfnoKs5T

I picked Keene, NH to work with because I don't know exactly where you are in southern NH. Here is info regarding frost dates in the Keene area.

Each winter, on average, your risk of frost is from September 17 through May 23.

Almost certainly, however, you will receive frost from October 1 through May 5.

You are almost guaranteed that you will not get frost from June 11 through September 2.

Your frost-free growing season is around 117 days.

data is from
http://davesgarden.com/guides/freeze-frost-dates/

I would suggest that you might be able to plant a short season corn variety ie. in the neighborhood of 60-65 days. Long season corn takes upwards of 90 to 100 days, and I think you'll run out of time.

OK, I'm gonna get a little geeky here!

I calculated the amount of heat that you can expect to receive between now and Oct 1. A ballpark figure for the amount of heat that corn needs from germination to harvest is in the neighborhood of 1400 GDDs.

On a historical average, you'll just barely have enough heat to get some corn if your weather is favorable.

Go for it!



Calculator can be found at
http://www.weather.com/outdoors/agriculture/growing-degree-days/03431

Thanks Bof!

I saw in another post you asked her where she was located; I just looked at the map to find a city in south NH, and decided to use yours. I don't know how close her weather is to yours.

On average, you get more heat in 3 months than I get in a year!

Sure, corn needs heat, but you need to plant a corn that is short season. I planted some 'Orchard Baby' it's only 3 ft tall and only takes 60 days. PM me and I can send you some seed. I got this yr. from Sand Hills Preservation Society and they always put more in pack than you'll ever need.

Jo

Awesome, thanks!!

Boffer,
I am curious, in a geeky way, how do you use the Growing Degrees Days Calendar? How can you figure out what are vegetables GDD?

The link doesn't exactly explain how to use it. Can you explain in a easy way to understand?

I am in a different zone.

Boffer, I also have a question about the degree day calculator. Why did you use 50 degrees as the base line temperature?

yolos wrote:Why did you use 50 degrees as the base line temperature?

Boffer has already educated me on this one so I can answer that. You don't get to select just any temperature for the base line. Plants have temperatures at which or below they won't grow. In general, 40 degrees for cool season crops, 50 degrees for warm season. Boffer chose 50 since corn is a warm season crop. I found this explanation on whyfiles.org:

Each day’s GDD is calculated by subtracting a reference temperature, which varies with plant species, from the daily mean temperature...

The reference temperature for a given plant is the temperature below which its development slows or stops. For example, cool season plants, like peas, have a reference temperature of 40 degrees F while warm season plants, like sweet corn and soybeans, have a reference temperature of 50 degrees F.

Thanks, Gwen, that's perfect!

GDDs are used by commercial farmers and greenhouse growers to plan for planting and harvesting activities. Insect development stages are also tracked to GDDs so farmers have a good idea when it will be time to spray their pesticides. I can't say that GDDs have improved my SFG gardening, but they answer a lot of questions.

For instance, Furballsmom is on the Oregon coast in zone 9A, and can't grow tomatoes without supplement heat. Ha-v-v is in zone 9A in southern Mississippi, and can't grow tomatoes in the summer because it's too hot. Zones are about winter temperatures and don't apply to annual veggies grown in summer. But if we look at GDDs, Furbalsmom gets about 900 per year, and Ha-v-v gets 5800! As I said above, in general, corn and tomatoes need about 1400 GDDs to reach maturity. You can see why Furbalsmom gets frustrated!

You can google and find a lot of info about GDDs, and the formula to calculate them is simple. I've spent hours looking for a list of GDDs by plant type, but they are elusive so far. One of our forum members is a small commercial tomato greenhouse grower, and she contacted her extension agent for me, but with no luck. If anybody happens to find a GDD list for types of veggies, please let me know. I'd love to know how many GDDs a heat loving plant like eggplant needs.

Sw. potato is 1200 heat units. I guess the formula may be different for different farmers and different crops.

formula

high temp + low temp, divide by 2, subtract 55 equals the heat units for the day.

25 units per day is as fast as the plant(sw. potato) can grow.

I guess this requires a high/low thermometer?



Jo

http://www.sandhillpreservation.com/pages/sweetpotato_catalog.html

THanks, Jo. The formula you cite is probably the most popular of the ones I've seen. I've not seen a baseline of 55 before, but that fits with my understanding that sw. potatoes don't like to get goosebumps.

You could track your own GDDs with a hi/low therm, or be lazy like me and plug in your zip code in the link I posted above.

I found a site that collects data from automated weather collection stations in the PNW. I like it because it displays data on a daily basis and presents a graph to compare current and historical data. It's a federal agency so there might be one in your neck of the woods.

http://uspest.org/cgi-bin/ddmodel.pl?spp=aaa&lot=50&hit=95&stm=1&wfl=C682909.txt&hfl=tacoma1_wa.txt&sav=1

That was an informative link, thanks. It also spells out why greenhouses work.

Hmmm, this relates to my ideas about when to plant based upon what feral plants are sprouting. It also shows a mistake I had... sunflowers and potatoes go together, wait a tad to plant the corn. This chart plus the GDD calculator explains to me why the okra is in wall o waters in the green house for the season. Interesting about the insects for this as well.
Table 1. Tbase for selected crops and insects
Crop Base Temperature
Corn, sweet corn, sorghum, rice, soybeans, tomato 50 °F
Cotton 60 °F
Peanuts 56 °F
Potato, sunflower 45 °F
Wheat, barley, rye, oats, flaxseed, lettuce, asparagus 40 °F
Insect Base Temperature
Alfalfa weevil 48°F
Black cutworm, European corn borer 50°F
Corn Rootworm 44°F
Green cloverworm 52°F

I have almost 1500GDD for warm weather crops. Which is barely enough for a small fruited early tomato, unless in a green house. And is not enough for corn at all. Welllll,,,, I kind of knew that from experience that corn was marginal at best.

Interesting discussion

I've been looking for GDD data for the squash vine borer. I'm thinking it would be helpful to know when to expect them, and perhaps starting vigilant watch, rather than waiting for their damage to show up to know.

boffer wrote:I've been looking for GDD data for the squash vine borer. I'm thinking it would be helpful to know when to expect them, and perhaps starting vigilant watch, rather than waiting for their damage to show up to know.

http://extension.umass.edu/vegetable/sites/vegetable/files/pdf/Veg%20Notes%20June%2028%202012.pdf

http://www.thewesterlysun.com/news/article_ee4a6ee4-8606-11e0-96e6-001cc4c002e0.html?mode=print

GDD for SVB is about 950 with 50*F base
I have been thinking along similar lines this season, one reason why I didn't plant out my squashes and melons earlier... I should have done more research on the subject.

That is really an informative website at umass for local conditions. Sweet!

If you grow Jubilee corn, you'll know when to expect certain plant growth milestones found in this chart.

Model species/general links: sweet corn [Jubilee];
Type: crop
Model source/other links: Coop et al. (1993)
Calculation method: growing degree-days - corn
Lower threshold: 50 degrees Fahrenheit
Upper threshold: 86 degrees Fahrenheit
Directions for starting/BIOFIX: date of planting
Starting/BIOFIX date: 5 1
Ending date: 8 31
Model validation status: partly validated
Region of known use: Pacific Northwest
==============================EVENTS TABLE================================
1. 104 DDs after planting: First emergence from soil
2. 308 DDs after planting: 5 leaf stage
3. 445 DDs after planting: 7 leaf stage
4. 883 DDs after planting: 5 inch tassels
5. 960 DDs after planting: 10 inch tassels
6. 1005 DDs after planting: 5% silk emergence
7. 1062 DDs after planting: 50% silk emergence
8. 1145 DDs after planting: 95% silk emergence
9. 1288 DDs after planting: 50% brown silks develop
10. 1412 DDs after planting: 95% brown silks develop
11. 1539 DDs after planting: Fresh market harvest
12. 1597 DDs after planting: Processing market harvest

Boffer, that's great! Where did you dig up that info?

I've had it around for a long time. Just happened to stumble across it today; my filing system leaves a little to be desired!