Cucumbers are a warm-season crop, and in Missoula that means you are working against the clock from the day you plant. The variety you choose is one of the biggest factors in how they do. Pick one bred for a long season and you may be harvesting your first cucumber right as the weather turns. Pick a fast, short-season type and you will be swimming in them by August.
The good news is there are plenty of cucumbers that finish quickly. The trick is reading the days to maturity on the seed packet and being honest about how much warm weather we actually get. Missoula’s median last spring frost is mid May (about May 16 at the airport, per NOAA’s 1991 to 2020 normals) and the median first fall frost is late September (about September 26), and cucumbers should not go in until frost danger has passed, usually late May into early June. MSU Extension’s tomato guide advises choosing very early varieties in mountain valleys with short seasons, and the same logic applies to cucumbers.
Look for Short Days to Maturity
Days to maturity is the number printed on the seed packet that tells you roughly how long from planting to first harvest. For direct-sown cucumbers it is counted from sowing, for transplants it is usually counted from transplanting, and it varies a little from one seed company to the next. A practical filter for Missoula is to aim for cucumbers in the 50 to 60 day range. That is a strategy for a short season rather than a hard cutoff, but anything much longer is more of a gamble in a cool summer.
Keep in mind that number assumes warm growing conditions. Cucumbers stall when nights are cold, so in a chilly June the real time to harvest can stretch out. Giving yourself a buffer by choosing a quicker variety is the simplest insurance you can buy. You can also get a head start with transplants started about 3 to 4 weeks ahead. Cucumbers do not like root disturbance, so handle them gently, and if you use peat or paper pots, make sure no part of the rim sticks up above the soil.
Best Slicing Cucumbers for Missoula
Slicing cucumbers are the long, smooth ones you eat fresh. For our climate, a few stand out.
Marketmore 76 is a widely grown standard with strong disease resistance. It takes about 63 to 65 days from seed, a little past that 60-day mark, and produces straight, dark green cucumbers. Purdue Extension notes it is listed as bitter-free. If you only grow one slicing variety, it is a solid choice.
Spacemaster is the one to grow if you are short on room or gardening in containers. The vines stay compact, but it still produces full-size slicing cucumbers in around 60 days. It does well in a large pot on a sunny patio.
Diva is worth trying if you want something a little different. It produces smooth, thin-skinned cucumbers without needing pollination, which means it sets fruit reliably even when bee activity is low early in the season. It matures in about 58 days and the cucumbers are crisp and nearly seedless.
Best Pickling Cucumbers
Pickling cucumbers are shorter and bumpier, bred to stay crisp. They also tend to mature fast, which makes them a natural fit for Montana.
National Pickling and Boston Pickling are both reliable, productive, and quick, usually ready in about 52 days from seed. They produce heavily over a short window, which is exactly what you want if you plan to make a batch of pickles all at once. Even if you are not pickling, these are good for fresh eating when picked small.
Bush Pickle is the compact option, a small plant that fits in a container or a tight corner of a raised bed while still giving you a steady supply of pickling cucumbers.
A Few Worth Trying for Something Different
If you have grown the standards and want to experiment, a couple of specialty cucumbers are worth a try in our short season. Lemon cucumbers are round, pale yellow, and mild, and the plants are vigorous. They are a fun one for kids, though at about 65 to 70 days they take longer than the fastest slicers. Suyo Long is an Asian type, about 60 to 70 days, that produces long, ribbed, sweet cucumbers, though it does best with a trellis to keep the fruit straight.
Whatever you grow, give cucumbers full sun, warm soil, and steady water. Bitterness comes from a natural compound called cucurbitacin. How much a cucumber has depends partly on the variety, and heat, drought or uneven moisture, and poor nutrition can all push it higher, so a bitter-free variety and steady watering both help. A trellis is worth setting up for any of the vining types, since it saves space, keeps the cucumbers clean, and makes them far easier to find at picking time.
For the full rundown on planting timing, spacing, and care, see our guide on how to grow cucumbers in Missoula.
Sources
- Montana State University Extension, Successful Home Vegetable Gardening
- Montana State University Extension, Growing Tomatoes in Montana
- Purdue University Consumer Horticulture, Cucumbers Bitter During Hot, Dry Weather