Spring is the time to get your grape vine cuttings started. You don't want to start them much earlier than mid-March as they need a long period of dormancy before they will come out of dormancy for rooting purposes.
I start my cuttings around the first week of April and that's often when I take my cuttings as well. Here is what I do to get the cuttings started indoors.
1) First - start with a 2-3 bud cutting. At the cutting ends it should show a nice green colour with lighter yellow green on the interior - this is a healthy part of the cane.
2)Stand the cuttings up in a cup or jug of water that goes half way up the cutting for at least 24 hours to allow the cutting to hydrate and absorb water. Remember the buds point upwards so it is easy to tell what end of the cutting is up and which is the bottom. The cuttings draw water from the bottom to top. See cutting below with bud that point upwards;
3)Prepare a 50/50 mixture of peat moss and perlite as a rooting medium to start the cutting in. You will also need small pots to plant the cuttings in. I like small clear plastic cups and you can put one cutting per cup. I like the clear plastic ones as you can see if the cuttings are rooting and how much roots have formed. You'll need to poke a small hole in the bottom of each cup so the water you put in will moisten the rooting medium but drain out. I use a power drill with a long thin drill bit and can stack about 20 cups together and drill all 20 at once. Its good to hydrate the cuttings for the first 24 hours but can't leave the cuttings in a soggy-soaked environment, they will rot - the drain hole is important.
4)Next take the cuttings out of the water and set them on a paper towel to allow the water to drain off of them.
5)Dip the bottom of the cutting into rooting hormone. I use "Stim Root #2" in the powder form with success but #1 may be better. Follow the instructions on the product. This is a rooting hormone that stimulates the cutting into producing roots. See below the rooting hormone I use;
7)Now, you'll want to put the cups on top of something that will warm the base of the cup. The cuttings will begin to root in soil that is warmer (this is also why you push the cuttings into the rooting medium to about 1" from the bottom). You can use a warming mat for indoor growing and can buy these from your local green house. I put my cups inside a small plastic container and put the container on the mat this way it contains the water that drains out of the bottom of the cups when you water them. I also put a thermometer between the cup so I can monitor the base temperature, which 24celcius - 27celcius (75f-80f) is ideal. See the plastic container used to hold the planted cuttings below;
8)Now water the cuttings in small increments for the first day to get the rooting medium nice and moist, then after that every few days when you see the moisture levels low. You want the rooting medium moist but not soggy.
9)Depending on the vine variety you may see the cuttings pushing buds out quickly within a few days and other between a week or two. See below as a bud is stating to push;
11)Once you have some nice roots forming and shoots growing well it is good to start introducing your vines slowly to the outside air and sunlight. I start by first putting them in a very shady area then slowly introducing them day by day to more sunlight. If you just put them directly into full sun they will wither and die. I also put them into larger pots that can hold more water at this time.
12)Once they are able to withstand a day in the sun they are ready to plant into the ground. Keep them watered but not soaked - they don't like to be soaked.
The other way to start cuttings is to just stick the cuttings into the ground. Wait till after the last frost before doing this. If you have taken the cuttings in late winter/early spring you may have to store them for several weeks before you can plant them. To store them I wrap my bundle of about 10-20 cuttings in moistened paper towel and then seal them up in a plastic bag. Then I store them at the back of my refrigerator where the temperature is about 0 c. I've planted cuttings this way and have had the cuttings produce vines but not as successfully as starting them indoors first. If you are just going to plant the cuttings direct to the soil, hydrate them first for 24hrs and also use rooting hormone. Stick them into the ground about 3-4 inches deep. I'd also make sure the soil stays moist. They will take much longer to grow this way and will be very small the first year vs. starting them indoors, but it is much easier and less labour intensive.