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Do you dream about apple trees laden with fruit, a freezer stocked with home-grown blueberries and frozen pomegranate juice, or cherry pies baked with cherries picked off the tree in your backyard? When the new seed catalogs arrive, do you stare longingly at the pears and figs and think about whether they belong in your front yard or if you should start an orchard? If so, you’ve probably seen the phrase “chill hours” buried in the description.

At its simplest, chill hours, also known as chilling units or chilling hours, measure the hours with temperatures below 45 ⁰F. Another measure uses hours between 32 and 45 ⁰F. The Utah Chill Unit Model and Dynamic Model are both more accurate and more complex.

Think about chill hours in terms of dormancy. During the first stage (acclimation), you’ve already harvested your crop and fall is setting in. Winter arrives just as your trees enter endo-dormancy. During this phase, it racks up chill hours. After it receives enough chill hours, it enters eco-dormancy and breaks bud. As temperatures rise above 40 ⁰F, it starts a new tally: growing-degree days. Once it’s received enough chill hours and enough growing-degree days, it assumes spring’s arrived and starts growing.

The good news is that until your tree receives the necessary chill hours, it won’t bud out. That’s also the bad news.

If you plant cherry trees in Florida, they’ll grow. The low chill varieties might produce a few cherries. Just don’t get your heart set on pounds of cherries picked from the cherry tree you’ve lovingly tended for the last five years. The same applies to growing oranges in Wisconsin. It goes double for the pistachio tree I’ve always wanted.

Find out your chill hours before ordering any fruit or nut trees and, preferably, before planning your orchard.

Finding Your Chill Hours

Call your county extension office. They’ll know the average chill hours for your area and may already have a list of recommended varieties with a proven local track record.

Another option is AgroClimate’s Chill Hours Calculator. Enter your zip code and set the chill hours model to 32-45 ⁰F. Then set the end date for the projected period to a year. (For instance, start 10/01/2018 and end 09/30/2019.) Under graph options, click display historical average and display last season. Now, select the USDA research station nearest you from the map and open the Total Accumulated and Projected tab.

Do you mind a little risk? Do you want the earliest possible fruit even if it means misting your precious apple blossoms with water at 5 AM to protect them from frost? Having done this, I don’t recommend the before sunrise (and morning coffee) water hose routine.

If you don’t mind installing an overhead sprinkler system or waking up before the rooster, choose 90% probability from your state’s Freeze/Frost Occurrence Data sheet. Otherwise, go with 50% or 10%. (The lower the probability, the lower the frost risk.) Scroll down until you find the nearest city to your location and note the frost date.

Now, find your frost date on graph. The green cone shows the estimated minimum and maximum chill hours. Mouse over the top and bottom green line for these numbers.

A large grower may select multiple varieties so his orchards produce even during low-chill and high-chill years. You see this a lot with peach farmers because even 100 chill hours plus or minus the ideal growing condition can impact yields. Gardeners and market farmers should focus on the bottom. Select varieties that need a few hundred chill hours less than your available chill. That way they’ll produce during even during uncommonly warm years. Then narrow them down based on whether they flower early, mid-season, or late. Ideally, you want them to bloom after your frost date.

A Real World Example

My childhood neighbor retired from farming and took up apple growing. He grew Anna’s, Dorset Golds, horse apples, and Fujis. Every spring, he gripped because his low-chill Annas and Dorsets always bloomed before the first frost. He spent many hours outside in the cold with a water hose. That region of Georgia receives about 400-600 chill hours every year. Anna apples flower extremely early and need less than 300 chill hours. His liked to bloom in February. Most years, his Anna and Dorset Gold trees produced gorgeous blooms and frost killed the apples before they grew. His prized Fuji apples featured in many an apple cake.


Anna (apple). (2018). In Wikipedia. Retrieved from

Chill Hours Calculator – AgroClimate. (n.d.). Retrieved October 23, 2018, from

Chilling accumulation: its importance and estimation. (n.d.). Retrieved October 24, 2018, from

Chilling Hours / First and Last Frost | Weather. (n.d.). Retrieved October 24, 2018, from

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How Cheese Is Made (Plus An Easy Farmer’s Cheese Recipe)

So, you finally have a dairy animal on your homestead! You’ve mastered milking and learned how to make your own butter and maybe even yogurt. What comes next? Learning how to make cheese right in your own kitchen is a skill many homesteaders dream of learning. Let’s talk about the basic of cheese making and an easy recipe for you to try at home.

How Cheese is Made

In the most basic of terms, the process of cheese making means merely separating the solids from the liquids by adding a starter culture to fresh milk. The culture causes the lactose in the milk to be changed into lactic acid. The lactic acid then causes the milk to curdle, separating the solids and the liquids. Certain types of cheese require an additional enzyme to coagulate the milk even further. The cheese solids, or curds, will then be separated from the whey (the liquids) by cutting the cheese into pieces and then pressing it into a mold.

For some cheeses, there will be an extended aging time of anywhere from a month or two to years in some cases, depending on how long it takes to achieve the correct flavor and ripeness. Cheese making can be a complicated process, but it doesn’t have to be. Simple cheeses like cottage cheese and farmer’s cheese can easily be made at home.

Types of Milk Used in Cheese Making

The methods used during cheesemaking, from how the curds are cut and which enzyme is used, to how the cheese is aged, all have an impact on the final product, and what kind of cheese you end up with. The type of milk also plays an important part. While cow’s milk is probably the most common, sheep and goat milk (and even buffalo!) are also quite popular. The important thing is that the milk is high in the protein casein, which makes the curds. Although certain types of cheese are most commonly made with milk from a specific animal, you can make cheese from the milk of any dairy animal you have on your farm.

  • Goat’s Milk: Goat’s milk is widely used in France for making many different types of cheeses. Goat’s milk is lower in potassium, which makes it safer for folks who have kidney disorders. It is also lower in lactose, so it’s great for people who have issues digesting cow’s milk.
  • Sheep’s Milk: Sheep are not usually the first animal that comes to mind when you start thinking about getting a dairy animal on the homestead. And, in fact, their milk is not often consumed just for drinking because it is very high in lactose, making it harder to digest. However, many favorite and delicious kinds of cheese are made from sheep’s milk, including Feta and Manchego.
  • Cow’s Milk: Cow’s milk is probably the most versatile milk of all, as long as you don’t have issues digesting it. It contains just the right amount of protein and fat for making all sorts of dairy products, and of course just for drinking. Cow’s milk is used to make mozzarella, cheddar, parmesan, and many more.

Making Farmer’s Cheese

You may know cheese by one of its many other names used in different regions of the globe. In India, it is called paneer. In Africa, they call it wagashi. Latin countries call it queso fresco or queso blanco. In fact, America’s cottage cheese, France’s fromage blanc, and Germany’s quark are all versions of the same cheese. The only differences are how much moisture is left in the cheese and which foods it’s served with.

If you have farm fresh milk, of course, that’s what you’ll want to use. It can come from a sheep, cow, or goat, and there will be a subtle difference in flavor depending on which one you have. You can even use milk from the grocery store, as long as it’s not ultra-pasteurized. You’ll need one gallon of milk to make about one pound of farmer’s cheese.

Rennet is often used to curdle the milk in cheese making, but in the case of farmer’s cheese, all you need is some lemon juice or vinegar. You will get a hint of the flavor from whichever one you choose. If that bothers you, you can also use citric acid (found in the canning section), which is almost flavorless.

Follow these steps to make your first batch of Farmer’s Cheese:
  • Gently heat one gallon of milk in a pan with a heavy bottom. Use a low setting and stir occasionally, so the milk doesn’t scald.
  • Once your milk reaches 180-190 degrees Fahrenheit, remove it from the heat. You can simply watch for the first signs of boiling (which occurs just above the 200-degree mark), or you can use a candy or cheese making thermometer.
  • Slowly add your curdling agent and watch carefully for when the milk begins to curdle. The exact amount you will need can vary depending on the properties of your milk. You’ll want to stop adding your curdling agent as soon as the curd form to avoid getting a sharp, tangy flavor. Let the pot sit for 20 minutes before moving on to the next step to allow the curds and weigh time to separate completely.
  • Line your colander with a piece of cheesecloth, set it inside a bowl, and pour your curds and why through it. There are lots of uses for whey, or you can simply give to your chickens, so don’t just pour it down the sink.
  • The next step is up to you. You can leave your cheese as is if you want it to be soft and spreadable. You could add salt and fresh herbs and spread it on soft bread or crackers. For cottage cheese, simply place the curds in a bowl with a bit of the whey. Or, if you want a slightly firmer cheese, tie the cheesecloth at the corners, squeeze out as much liquid as you can, and then hang it over a bowl to continue draining off the whey.

If you want a very firm cheese you can slice, place the cheesecloth wrapped curds and colander in your refrigerator overnight with a weight on top. Be sure to put a bowl underneath it to catch the whey. Try rolling your pressed cheese in cracked pepper of chopped herbs to serve on crackers.

Farmer’s Cheese is best eaten fresh. Use it up within a week to 10 days and store it in your refrigerator.

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