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England

Hi everyone! I would really appreciate some advice on pollination, as for the last two years my pumpkins have grown beautifully, but with one problem. The female flowers grow, hang around for a bit then drop off, followed a week or 2 later by the male flowers. I never seem to have male and female flowers together and as a result I have not yet managed to grow a single pumpkin! I'm going to have one last try this season, what do you recommend I do if the same problem occurs?
Thanks!!
Lisa

2/27/2004 6:09:09 AM

Ctpumpkin@optonline.net

Lisa,

There are many factors to consider here.

We had the opposite problem here last year. Caused by my own heavy hand applying gibberelic acid (a plant growth hormone) at 4 times the recommended rates just prioer to flowering. All male flowers for 5 weeks.

As such I've spent quite a bit of time & energy researching this subject.

Several things we'd need to know:

1.) Were these desirable seeds from a reputable source such as might be obtained from the growers here?

2.) Were any of the popular seaweed extracts applied during or near the flowering period? Which one(s) & how much?

3.) Have fungicides been used at or around the flower developement period? If so, which one(s)?

4.) Are there any trees near enough to the patch to either send roots into or cast a shadow over it? What species & how close?

5.) Do you recall seeing any chew marks or scratches on the fallen females?

While published studies pertaining specifically to our beloved Atlantic Giants are few & far between, there are enough data available on other Cucurbita sp. to draw some solid conclusions on this matter.

For sure we can influence flower quanitities & schedule with PGRs whether intentionally or accidentally. Timing & rate data are scarce but we have some ideas.

There are other likely influences such as temperature that can swing things around too. Propoconizole fungicide has a growth regulating effect on most flowering plants & cucurbita is not immune from this effect.

Then again, simple fruit rots could be damaging the females & causing them to abort. Garden slugs & Squirrels like to chop off the young females too.

Fun hobby isn't it? LOL

Steve

2/27/2004 8:13:36 AM

Ctpumpkin@optonline.net

Oh yeah! Easiest question of all.

Are you hand pollinating them or leaving it up to the Bees?

2/27/2004 8:17:52 AM

England

Hi Steve!
The seeds were Atlantic Giants from Thompson and Morgan, bought fresh each year. I germinated them inside and planted them out when all frosts had passed, they were about 6" tall and looked lovely and healthy. I dug out a 3' x 3' x 3' hole in a sunny spot sheltered from the wind for each seedling (there were two), filled each hole with standard potting compost, kept them well watered and fed with Tomorite (I think this is seaweed based but I'm not sure!) once a week. The only animals we're really troubled with are cats, and they've learnt the hard way about scratching in my beds so don't see many of them in the garden!! Each flower had a lovely ball behind it that grew to about the size of a golf-ball before rotting away, so frustrating!! I grew 2 bush marrows on the same plot, and they performed a treat, I hand-pollinated those and would have hand-pollinated the pumpkins if the males had been around at the right time Phew!! That's all I can think of, looking forward to your reply,
Lisa

2/27/2004 1:17:16 PM

Ctpumpkin@optonline.net

OK. Start sending out the Private emails with requests for better genetics. Start by emailing us here. Click the envelop above my screen name & include a valid mailing or PO Box. I have enough bubble left so don't bother with the SASBP.

I'll route around for information abot that fertilizer later. Do you recall the rate used? Young plants that are about to set fruit don't like to be fed as a rule, So we coulkd be on to something already.

More later

Steve

2/27/2004 2:50:53 PM

England

That was quick, thank you!! I've found the fertiliser, it's an NPK 5:5:10 ratio and says "Recommended for use on tomatoes, marrows and aubergines", so I took a gamble on it being ok for pumpkins as I couldn't find one anywhere that specified being suitable for pumpkins (these were pre-pc days!), was that a mistake? I started feeding them every week approximately 4 weeks after planting, when I started to worry that the potting compost was running out of nutrients.
You're right, this is a fun hobby, I'm getting really excited now that this might just be the year I manage to grow one!!

Lisa

2/27/2004 3:59:45 PM

In the shade - PDX, OR

I would suggest contacting Alun and AXC as they are some what local for you. - at least in country. (check the '03 grower diaries for contact info)

Both of these guys are accomplished growers and I bet they would be happy to share some seed.

Sometimes it is most difficult to coordinate male and female flowers opening on the same day. Best to try 2 plants so you have 2 shots at getting males. If 2 is not a option try to convince a neighbor who gardens to plant an AG. That way if you are in a bind for pollen, they also might have males available.

Welcome aboard!

2/27/2004 5:03:42 PM

To me, it sounds like your females just aren't getting pollinated. When you know the female flowers are going to open soon, you can start picking the male flowers the night before they look like they're goign to open, and put them in the fridge. Then just take them out if the fridge the night before your female flower will open, and then use them to pollinate with. The female should be pollinated the morning that it opens. If it's going to be really hot that day, some people like to shade or cool their females so the heat doesn't interfer with the pollination being successful.

2/27/2004 6:45:54 PM

Ljubljana, Slovenia

I guess it may be the genetics, because my cousin had an all female plant in the patch with several normal ones. So, by planting two genetically different plants you should be OK.

By the way Steve, giberelic acid was first discovered in a fungus (“Giberella”), because it induced abnormal growth in grass. The result of your (unhappy) experiment supports the possibility that all female symptoms could occur because of a similar fungus in the soil.

Good luck!
Jernej

2/28/2004 9:42:04 AM

Ohio, USA

Maybe you could grow a different variety of pumpkins that are compatible with AGs such as casper or luminas and use them to pollinate the AG females. When I grew Casper pumpkins I noticed there was no shortage of males at all.

2/28/2004 11:02:50 AM

England

Hi guys!! Thank you so much for all your advice, hopefully now this year I'll get lucky! What are Casper pumpkins? If I lose the pea/bean patch (and possibly the carrot patch) then I'll have room for one other small pumpkin vine alongside the two AG's I'm hoping to plant. Or should I just plant one AG and one other variety? Thanks for all your good wishes!

Lisa

3/1/2004 3:16:14 PM

Garden State Pumpkins

Hey Lisa, If your pumpkins are growing in an old garden especially of peas or stringbeans I suspect you have pathogens in the garden...the plants will grow but the pumpkins will never come...fusaria, alternaria and gummy stem blight will significantly degrade even if the males are present...check and see if the fruit developes any black spots on them as they age....good luck if it's an old garden your better of moving off that spot until the pathogens go away...especially replanting last years seeds from the peas and stringbeans! highly contagious and spread the pathogens.

3/1/2004 6:32:09 PM

Garden State Pumpkins

oh yeah been there done that!!

3/1/2004 6:35:01 PM

England

Aha!!! The pumpkins were grown directly next to a combined patch of string beans and peas, and I have saved some seeds from last year that I was intending to grow that I shall now throw away. I'll have to grow them on an allotment (community plot?) instead this year as I only have one place in my garden suitable for pumpkins, it will be the first time it's been used for years, so the ground should hopefully be nice and clean. I've spent the last year clearing the nettles and brambles, digging it over and conditioning the soil, and it's just about ready to be planted. Off topic slightly, I didn't realise that pumpkins were one of the 14 most health-beneficial foods, I read it in a newspaper this morning in an article that was accompanied by two delicious recipes. Fun and healthy, what a cool hobby!!

Lisa

PS: Alexsdad, my eldest is also called Alex!

3/2/2004 4:32:17 AM

Ljubljana, Slovenia

This bean thing is interesting because the vine that grew together with beans had stem lesions and aborted the fruit. Besides that I strongly suspect that the virus which terminated my last season came from the same bean plant. No beans this season!

3/2/2004 6:44:49 AM

Garden State Pumpkins

Only problem with fusaria is the pathogen will stay alive for up to four years without a host...fallow for four years is a long time when you only have one patch...any vining plant will maintain it so crop rotation to onions or carrots would be ok....tomatoes beans cucumbers anyththing that vines will only continue it...a soil sterilant may be needed to knock it out.

3/2/2004 7:24:28 AM

Ljubljana, Slovenia

Damn, I checked the net and now I am sure I have Fusarium in the garden!!! There were typical symptoms also on basilica and tomato plants. Alexdad, what soil sterilant do you suggest?

This is a description of the disease on www.ext.colostate.edu/pubs/ Garden/02949.html

Fusarium wilt and Fusarium crown rot begin as yellowing of older leaves. With Fusarium crown rot, the leaves often turn brown or black and eventually wilt. With Fusarium wilt, the yellow leaves turn downward and droop. Fusarium oxysporum, the cause of both diseases, is a common fungus that lives in the plant's vascular system, which carries water from the roots to the leaves. To see if either of these diseases is present:
„X Check watering practices. Both over- and underwatering can mimic disease symptoms.
„X Check the roots. Discolored roots indicate root rot.
„X Cut the lower or main stem and look inside at the vascular tissue. Fusarium wilt causes a dark brown discoloration within the vascular tissue. Fusarium crown rot causes a rot or canker at the base of the stem and possibly a root rot.

3/2/2004 10:29:19 AM

Garden State Pumpkins

Yo UJ...I really hope it's not fusaria...but soil fumigation basamid might be a way to go...trouble is that the soil temperatures have to adequate for application then two weeks of solarization with the patch covered...will usually put you well past the planting time you want...After two years of nothing I did tissue samples and confirmed the pathogen...so I moved the patch out...treating the soil virtually removes all living things and will have to be innoculated with some good stuff to get it back on track...good luck...Chuck

3/2/2004 2:55:43 PM

Ohio, USA

Casper pumpkins are white pumpkins with an orange flesh that weigh 10-20lbs. I grew them last year and found them fairly easy to grow.

3/2/2004 3:02:49 PM

Ctpumpkin@optonline.net

If you must gas, then Basamid is the way. But wait until after this season. If you see disease symptoms developing this year, immediately get a sample to a plant pathology lab. If you have a positive, then you might decide to treat. End the season early while the soil is still warm. Then move forward. Soil borne diseases must be in active respiration to be controlled.

Basamid is a bog deal. Reestablishing good soil biology afterwards is part of the process. We can guide you if or when the time comes.

Steve the BASF certified Basamid specialist (I still think that's funny)

3/2/2004 8:45:03 PM

Ctpumpkin@optonline.net

Big deal. Basamid is a BIG deal. As in not to be taken lightly like my proof reading.

3/2/2004 8:46:18 PM

Ljubljana, Slovenia

Thanks for info on soil treatment. Sure I will first take the samples to specialists. Last season brown cracks developed on a vine that was growing in the most humid part of my garden and was also injured two weeks before:
http://www.bigpumpkins.com/Diary/DiaryViewOne.asp?eid=11373

Only one vine was temporarily affected but stump galls developed massively. The latter may be also because of virus infection.

I have a small garden where everything is recycled for 20 years already. There sure is a huge diversity of microorganism but still I believe that the good outnumber the bad. For this reason soil sterilization is not a good option. So, this is my plan:
1. cover the soil in the spring with thin layer of lime and let it rest for some time
2. eliminate other plant hosts (beans, tomato)
3. avoid physical damage to vines
4. avoid misting
5. keep other diseases away (especially viruses)
6. HOPE and WAIT

If this doesn’t work I will consider more radical approaches next year. Thanks again, Jernej

3/3/2004 3:53:10 AM

England

Although the symptoms sound horribly similar to the ones I saw in my pumpkin vines, I'm going to keep my fingers crossed that my soil isn't infected with this Fusaria thing as my marrows and my one cucumber vine weren't affected and cropped well. I looked up the Casper pumpkins and am going to get hold of some seeds, as they have to be the prettiest pumpkin ever (unscientific, I know, but hey I'm a girl!!). I'm going to post a diary with photos of all the vines as they grow, if it looks like I'm having the same male/female problem, would you guys be happy to advise?
Thank you so much for all your advice, and Tremor, I'm sorry if I offended you with my bad etiquette!!

Lisa

3/3/2004 5:54:12 PM

England

Jernej, I really hope you get your garden up and running at full strength again soon, it's so frustrating when one only has a small patch and it becomes "plant-sick". I had to take on my allotment for the same reasons, a small garden that had been cultivated for many years and didn't have much left to give, bless it!! By the way, are you an Olympia fan?

Lisa

3/3/2004 6:30:58 PM

Ctpumpkin@optonline.net

Offended me? By what? I must have missed something. But not to worry. I cannot be offended.

Lisa, have you gotten my emails for a more complete mailing address? Or is our firewall blocking your smiles?

If you have return-emailed me, they're not going through.
So try:

ljepsen@optonline.net

Steve

3/3/2004 6:59:41 PM

England

Lol! I'm so relieved, call me silly but I was a little worried!! I've just sent you a mail with the relevant details, let me know if it didn't come through to you.

Lisa

3/3/2004 7:20:32 PM

Appalachian Mtns.

Bet I could offend you Steve, just wait and see if you bunk in my room at Niagara....haven't you heard, us Southeners are knarly!

3/3/2004 8:18:06 PM

Norton, MA

lol!

3/3/2004 8:44:36 PM

Ljubljana, Slovenia

Lisa, I believe that in a small-long running garden it is still possible to grow well if good microorganisms balance over the bad. You can help to keep such balance by fertilization with organic manure and avoiding excessive mineral nutrients.
The point is that beneficial microorganisms, such as mycorrhizal fungi, help the plant to fight various stresses including diseases. These beneficial plant-microbe interactions are very sensitive to over-nutrition; moreover in such conditions bad microorganisms overgrow the good. So, keep on adding good organic manure to your patch!
Last year I over fertilized my pile with chicken manure which has a lot of nitrogen and I believe that this deteriorated the microorganism balance in the soil. In spite of that, only one vine (and critically the stump) was affected, which means that the plant still managed to overcome the disease. This season I will try to improve the soil balance and the plant should be able to help itself – with some help from beneficial microorganisms.

How do you know Olimpija!? Yes, I watched the basket game yesterday though we lost to Bologna. Good luck! Jernej

3/4/2004 3:44:55 AM

England

Oops, I've put my foot in it again, when I asked if you were a fan I was referring to the UEFA Cup, and have just found out that they lost, sorry! I think I'll stick to talking "garden" in future!!

Lisa

3/4/2004 5:18:07 AM

Ljubljana, Slovenia

No problem, it`s only a sport

3/5/2004 11:41:14 AM