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ejr2005

Last Hard Frost Date?

ejr2005
12 years ago

How do you find out the "normal" date for the last hard frost? I know this year isn't normal, but ...

Comments (29)

  • ejr2005
    Original Author
    12 years ago

    Thanks pixie lou! Got it from plantmaps.com. I was seeing maps but we're at a lot of the borders - just off 128 - and I couldn't differentiate the colors. I could put in the zip code at that site and voila - we're May 1-10. I'm thinking this year especially that's probably a good date to stop worrying. I don't usually worry about spring freezes, but this year my plants are so confused by this weather - as am I.

  • mad_gallica (z5 Eastern NY)
    12 years ago

    This is a lot more information than you asked for, but some people may find it useful.

    There are actually as many frost/freeze maps as people want to define. The usual variables are what temperature is being looked at, and how likely it is for that temperature to happen. For me, a hard freeze occurs are 28F, not 32F, even though most hardy perennials seem to have little trouble with temperatures that warm.

    The second variable is how likely is that temperature to occur. An average frost date means roughly that it is as likely to frost after that date as it is before. While it might be useful for farmers who could potentially charge higher prices for an earlier crop, it is less useful for home gardeners. So the number that is usually talked about is 10%.

    Here is a link that might be useful: NOAA frost maps

  • ejr2005
    Original Author
    12 years ago

    Thanks mad gallica - that's great info too. I could zoom on on those maps to read them. It's weird - we're in Metrowest and in the May1 or after date for 10% or less probability but south of Boston (and pretty close to us) is in the May 15 or later box. I would think it would be the opposite. Anyway, by early-mid May we should have more clarity from the weather forecasts.

    I'm most concerned about some baby hydrangeas that I had in the garage all winter. They're already leafing out - don't know what they'll do before mid May. We're be away a lot before then, so I'll have to leave them in the garage for some long stretches.

    I also have one hosta that I thought was dead - it lost all it's leaves early last summer. Now it's leaves are about to unfurl. I'm not too worried about that thought - a couple of years ago I had a hosta in the garage that I forgot about for at least one summer if not two. I was experimenting to see if I could get rid of it's foliar nematodes. When I found it it had very large very white leaves. It's now thriving with no nems that I've seen.

  • WendyB 5A/MA
    12 years ago

    There is a cold spot that the weather folk always talk about I think down by the Taunton/Norwood general area. I think its due the low-lying aspect of that area??? Up in northern middlesex county close to NH, we go by May 31st, but I usually bump that by 2 weeks and just be careful. I think this year, I will bump it to May 1st and just keep watch. Will see how April goes.

    You would think that shrub foliage could handle a little frost, but you are wise to protect it. I have had Hydrangea foliage damage in the past from late frosts. Its not pretty.

    If you have a warm south-facing spot up against your house, that might be a good place to put borderline plants for now.

    I have a 5' shelf setup loaded with potted perennials overwintered from the garage and elsewhere. There is a small amount of foliage. I don't plan on any extra protection, although it would be easy enough to throw an old sheet over the whole deal overnight. Maybe I will. But if I were traveling, I would just leave them alone.

  • ColleeninMHD 6a
    8 years ago

    In this mild winter, do you think our last frost date will be more like April?

  • NHBabs z4b-5a NH
    8 years ago

    IME, I wouldn't count on it being different than usual. It is an average, so it might be earlier or later, but I haven't noticed a pattern as to how cold the winter is as related to the last frost date.

  • prairiemoon2 z6b MA
    8 years ago

    Right now, I have daffodil foliage that is above ground by 6 inches. At the same time, Hellebores that evidently bloomed when I didn't notice and must have gotten smashed by the snow we had, so I'm wondering if they will rebloom at all. In that one particular area, they are not looking good, but on the north side of a fence on our Southern lot line, the Hellebores are doing okay. Starting to show foliage and buds, but it seems very early to me.

    I'm just happy to have a few opportunities to clean up and get ready for the growing season. I don't know if I'll plant out early or not. I may sow some seed for lettuce, peas and spinach earlier than usual this year.

  • NHBabs z4b-5a NH
    8 years ago
    last modified: 8 years ago

    PM2, I do sow cold-tolerant crops earlier if it warms up early since they can tolerate frost and the soil will be warmer, but I don't much like taking chances on my frost-tender crops since if they die back I may not be able to find plants to replace them.

  • defrost49
    8 years ago

    My husband thinks we might get a blizzard later in March. I remember one town meeting where the road crew was out plowing. The daffodils next to the house are up about 2-3 inches. I might rake the herb garden off since chives can come up very early. So many things affect date of last frost. We get an early,light frost around mid-September but we are at a low elevation with open fields. People a mile away are higher and don't get that early frost.

  • prairiemoon2 z6b MA
    8 years ago
    last modified: 8 years ago

    Barb - I agree with that approach. Especially after babying them for a month plus. [g] Do you have cold tolerant transplants that you'd think about putting out early? All the Brassicas?

    Defrost - I seem to remember having snow in April a few years back and having bare root roses that were delivered that I had to store in the refrigerator for 10 days. I'm surprised that my daffodils at the back bed which is exposed to winds, have the daffodils that are up the most. I'm thinking they are the earliest blooming varieties I have.

    We don't get an early frost here in the Fall, but when the sun's angle is lower, it dips below the tops of the surrounding trees and we find our vegetable plot really deficient in sunlight in the Fall, so not much of a fall season for us here either.

  • NHBabs z4b-5a NH
    8 years ago

    My cold tolerant early crops include some greens such as spinach, kale or lettuce. I don't plant broccoli early since it can cause problems with head formation. I also plant peas (presprouted) as soon as the garden is thawed and the chance of snow is over; I think the first week of April is the earliest I can do here. I also sometimes plant chitted potatoes around the time I plant peas.

  • defrost49
    8 years ago

    prairiemoon, I use Agribon fleece cover on bush beans and broccoli to protect them from that early frost although broccoli is pretty hardy. If beans are still blossoming at that point and get protected, I can have another bean harvest. First week of April is my target for planting spinach direct to the garden. I should have some in my high tunnel but some kind of large furry critter burrowed in late last summer and decimated what I had planned to over-winter. Burrow was underneath some tomatoes so I didn't see it until I pulled the tomato plants. My husband put out a homemade trap yesterday but nothing yet. I'll also put an early planting of potatoes that have sprouted in the high tunnel. Yes, we've had April blizzards.

  • spedigrees z4VT
    8 years ago
    last modified: 8 years ago

    My first thought when I looked at this thread was: PixieLou, you're back!!! But then I looked at the date on this post. :-( However it seems that even in a cyber-posthumous state, she is imparting useful and unique info and ideas!

    These maps are great. As I had long suspected, I live in a small pocket where the average last frost is June 1 - June 10. I have always felt that my zone verges on 3, rather than the zone 4 that less detailed maps ascribe to me. Now I have proof!

    Back a few years ago they changed Memorial Day to an earlier date, and I naively didn't notice, and lost plants to frost. Since then I treat June 1st as the day plants go outdoors, and perhaps even that is a week too soon.

  • prairiemoon2 z6b MA
    8 years ago
    last modified: 8 years ago

    Barb - I haven’t tried pre sprouting peas yet. Maybe I should try that. I used to try to shoot for St Patrick’s Day, for peas, but I haven’t been able to do that except for a few years. I have winter sown containers out there, and spinach is the only one that has sprouted. But I still think it’s too early to plant that out.

    What’s a chitted potato?

    Defrost - Do you start bush beans early? Maybe you mean you cover them in the fall, when they are already growing? I do have Agribon, so that is an option. I wish I had a cold frame or two and I think that would go along way to helping to get things out just a little earlier. I don’t have room or enough sun or the energy to put up a tunnel. I wish I did.

    Are you zone 5? Perhaps I should be considering the last week of March, here in zone 6 for sowing spinach.

    Spedigrees, that is sure a short growing season for you. Can you grow tomatoes and peppers to a ripe stage?

  • NHBabs z4b-5a NH
    8 years ago
    last modified: 8 years ago

    PM2, Chitting potatoes involves setting them out indoors to let the sprouts green up a bit, usually for 2 or 3 weeks. I prop mine up in an egg carton on the dining room table since it's a nice bright area. They don't actually start growing, but the buds swell and the tiny emerging leaves turn a nice rich green. Then I plant the potatoes in a 6" deep trench and lightly cover them with soil, and then when they start to actually grow, I fill in as the stems elongate. It is supposed to give them a head start, and I often dig my holes early so the deeper soil has a chance to warm up also.

  • prairiemoon2 z6b MA
    8 years ago

    Sounds like you are right on the cutting edge, Barb! I haven't tried potatoes, this will be my first year. So are these sections of potatoes you ordered?

  • defrost49
    8 years ago

    sorry for the confusion Prariemoon, yes, it's a late planting of bush beans that I'm trying to protect from a fall frost. Last year we spent 4th of July weekend in Maine's Ellsworth area. I found a wonderful nursery that was selling beautiful 6 pack of veggies. It seems the summer people were just starting their vegetable gardens.. I bought broccoli plants which didn't mature until late. I put the Agribon right over the plants but hoops are better. I have some wire hoops that I can just stick in the ground. I have a portable low tunnel covered with Agribon but it takes too people to put it in place. It works better to put over a seedling bed in the spring. Last year I also put Agribon over winter squash plants when striped cucumber beetles showed up. It stayed on until mid-July and the plants grew fine with the cover/no hoops. I'm just north of Concord NH so in the colder edge of zone 5.

    NHBabs, great tips on chitting potatoes and digging a trench early to warm up.

  • NHBabs z4b-5a NH
    8 years ago

    PM2, sometimes I use potatoes from the previous year and sometimes I order new. After trying 15 or so varieties over the years, we have pretty much settled on 3 varieties: Russian Banana, Butte, and either Yellow Finn or Yukon Gold. RB is the largest fingerling I have ever seen, up to real banana size. It's yellow fleshed and waxy in texture so it doesn't crumble in stew and is wonderful roasted. Terrible in mashed or potato soup, however. Yellow Finn produces better than YG, but isn't as attractive - sort of lumpy looking. Both are good for mashed, soup and roasted. Butte is a russet so is great roasted and baked and is also good for soup and mashed.

  • prairiemoon2 z6b MA
    8 years ago
    last modified: 8 years ago

    Defrost - Last year, I had trouble with Cabbage moths in the Brassicas and the only agribon I had was ripped, so I ended up just letting them go, but it was so funny, I started seeing wasps and yellow jackets patrolling the brassica beds and I saw a post on the Vegetable forum that indicated that they were after the larvae of the cabbage moths. I saw the moths, the wasps, then no damage to any of the plants. It was amazing. I’ve also had the same situation with aphids and lady bugs. I now have it in my head, that the way to control bugs, is to allow them to multiply enough to attract some beneficials that take care of them. Of course, I have a tiny yard and garden, and what might be working well for me, might not always and certainly would be different on a large property.

    Thanks Barb, I ordered 2 lbs of Purple Viking potato this year, because I loved the color of them, and I’m just going to give them a try and see how it goes. If I find I’m able to have decent results, I may order the sample pack at Woodprairiefarms next year. All those varieties sound great.

  • NHBabs z4b-5a NH
    8 years ago

    PM2, I ordered purple potatoes one year, though it was long enough ago so that I no longer know the type. When cooked the purple turned a bit grayish, and the flavor and texture was sacrificed for color. I hope your experiment with purple color is tastier and more appealing.

  • prairiemoon2 z6b MA
    8 years ago

    I hope so too. I did talk to two people who have grown it and enjoyed it, so I guess we'll see.

  • defrost49
    8 years ago

    A friend in Missouri raved about the Purple Vikings she got in her CSA. I recently saw a photo and thought I should have tried them. I got Purple Mollies (I think) in my first fingerling sampler pack - purple all the way through. I thought our granddaughters would love them but everyone, including me, was turned off by the color. Which is too bad because they are more nutritious.

    PM2, I'm glad the insect problem at your house worked out to be successful. I know from past experience that certain summer squash don't seem to be attractive to striped cucumber beetles and squash bugs but I have been having trouble growing zucchini lately and didn't want to lose my winter squash. I patrol the potato patch to handpick bugs and try not to use any non-organic insecticides. I left wasp eggs on tomato horn worms and haven't seen horn worms for the past two years so that might have worked. We also have an unmown strip of wild grasses and whatever grows next to the vegetable garden and some flowers and herbs mixed in to attract beneficials. BTW it works better to knock potato beetle larvae into a container of water than to try squishing them all.

  • kitasei
    8 years ago

    I'm intrigued by the chitting potato discussion. Can I do this with some yukon gold potatoes I buy at a supermarket - or organic market?

  • mad_gallica (z5 Eastern NY)
    8 years ago

    We regularly buy purple fingerlings at the farm market. Roasting them in the oven is the way we usually cook them, though I believe DH has made potato salad.

  • defrost49
    8 years ago

    Supermarket potatoes may have been treated with something to prevent spouting. I would try organic but if you have a farm and feed store nearby, that's the first place to look.

  • prairiemoon2 z6b MA
    8 years ago
    last modified: 8 years ago

    Here's the Purple Viking and the interior is white.

    Defrost, I would definitely use the Agribon if I have trouble with cucumber beetle. I had them a long time ago and they are quite hard to deal with. I stopped growing squash for awhile. Nice to have a place for an unmown strip for beneficials. I keep trying to add plants that attract beneficials, but I never seem to have enough.

    MadGallica - Thanks for the tip on using the purple potatoes.

  • spedigrees z4VT
    8 years ago

    Prairiemoon, I love the appearance of those Purple Viking potatoes! If I were to grow potatoes, that would likely be the variety I would choose, either those or one of the red varieties.

    Yes I do have a very short growing season here. I think I misread the map though. When I zoomed in closer, the Jun 1-10 (last frost dates) area is slightly south of where I am, but the May 21-31 is definitely overly optimistic. Usually our last frost fall right on or about May 30th. Jun 1st is typically the safe bet for plants to go out. Also -20 F is commonplace here in winter, and -30 happens sometimes.

    Years ago I used to buy tomato plants, and then I started my own from seed indoors a few times. Then the late blight hit and I gave up growing tomatoes. I tried growing pimento peppers from seed last year and that did not go well, so I've given up on peppers for now. I'm an easily discouraged gardener!

    Like you, defrost, we have deliberately unmowed areas where a variety of wildflowers grow. I chop a few undesirables like burdocks and poison parsnip, but mostly let nature take its course. I even let stinging nettles grow since I learned these are caterpillar food for black swallowtail butterflies.

    Several of our unmowed areas are in places where I have seedling trees planted, so eventually these will transform from meadow land to wooded areas. I'm trying to plan ahead to keep my remaining strips of unmowed land far enough away from the growing trees to avoid being shaded. The milkweed and other plants that attract beneficials need strong sunlight to grow.

    In the here and now however, the striking absence of a variety of insects and other creatures last year is alarming, even with abundant food supplies. I believe I saw only 3 or 4 monarch butterflies all last summer, very few honeybees, and zero barn swallows. No one near me uses pesticides or herbicides, but a lot of the former visitors to my patch of ground are migratory, so I imagine other parts of the country are less eco friendly than Vermont.

  • defrost49
    8 years ago

    Don't worry, the barn swallows and tree swallows are at our house. Sadly, we have very few bats because of the white nose disease. I think my husband's mowing practice has changed things even though it's only once a year, usually in August. We had to rope off one area because we were pretty sure a bobolink was nesting there. But we have far less milkweed than we used to. I visited a permaculture homestead in NH that always leaves a different area unmowed for a year.

    I've been having problems with tomatoes which seems to be related to rain splashing on unmulched soil. I tried black plastic in one area which did better than a section where I used grass clippings. The tomato plants (and peppers) in my high tunnel with the plastic sides rolled up did terrific. I did not expect to put the high tunnel to so much use during summer but all my peppers went in there last summer and did well. I think they also liked the additional heat because even with the sides rolled up, it would get in the 90s on a sunny day. I grew mostly bells, one or two poblanos and jalapenos. This year I am trying out more hot pepper varieties.

    My winter squash patch started off being covered with black plastic because of a creeping jenny weed. Once the plastic killed the weed, it was easy to grub it out. I guess the soil also got warmed up. I'll put the Agribon over the row again this summer as soon as the plants get a good start. That combination might have been why I had my best crop ever.