Hardening Off Vegetable Seedlings for the Home Garden (2024)

FAQs

Hardening Off Vegetable Seedlings for the Home Garden? ›

The easiest way to harden transplants is to place them outside in a shaded, protected spot on warm days, bringing them in at night. Each day, increase the amount of sunlight the transplants receive. Don't put tender seedlings outdoors on windy days or when temperatures are below 45° F.

In general, begin the hardening process 7-10 days before the date you intend to plant them out in your garden and once the danger of frost has passed. If your growing zone generally recommends that starts don't go outdoors until the last week of May, begin hardening seedlings a little more than a week before.

Problems. The most common problem is damage from cold temperatures, or even a late frost. If this happens, cut out the damaged growth and continue to harden off. In warm weather pests such as greenfly might multiply and need controlling.

As the name suggests, warm season crops such as tomatoes, peppers, zucchini, and cucumber prefer warmer weather and are less cold hardy than cool season crops; these are the plants that hardening off is most important for. Warm season crops should not be transplanted outside until after the last frost for your area.

The rule of thumb for hardening off tomato plants is one hour outside on day one, two hours outside on day two, and so on until the plants are outside for the entire day. Given weather conditions, this process can often take a week or more to complete. Keep young plants out of direct sunlight to avoid sunburn.

Hardy plants can be hardened off when the outside temperature is consistently above 40° F. Half-Hardy plants may be hardened off at 45° F.

Late spring is the time to start thinking about moving your tomato plants outside. Begin the hardening off process 7-14 days before the date you plan to transplant your tomatoes outdoors.

Without proper hardening off, seedlings may experience stunted growth and premature bolting from temperature stress. Even if temperatures don't dip below freezing, seedlings can still suffer damage from dropping temperatures and the cool, wet conditions typical of spring evenings.

When do I leave the seedlings outside all night? If temperatures are above freezing, allow plants to stay outdoors overnight after several days of hardening them off. For warm-season crops, bring them back indoors if temperatures are cold. If it is warm outside, you can leave them overnight after the first few days.

What is the most difficult vegetable to grow? ›

1: Artichoke

Due to similar climate conditions, artichokes work well as perennials in northern California, but may be difficult to grow as perennials in other areas of the nation. Since artichokes like moderate conditions, grow them as annuals in cold winter and hot summer areas.

Before planting, harden off your zucchini (acclimatize them to the outdoors) by placing them outside for increasingly longer spells over the course of about 10 days. Don't be tempted to cram plants in.

Now that you have started your seedlings from the brassica family (cabbage, kale, broccoli, kohlrabi, cauliflower, collards, and brussels sprouts) indoors, it's time to harden your 3 to 6 inch seedlings by temporarily moving them outdoors so that they will get used to natural daylight and temperature fluctuations; as ...

If your seedlings are off to a less-than-stellar start, you may be able to save them. Insufficient light is the most common cause of leggy seedlings. If your seedlings are getting enough—but not too much—water, and it's not too cold, try adding more light.

Consider using clean, lukewarm water on your seedlings. Water from underneath rather than overhead, keeping the leaves and top soil layer dry. For outdoor gardens, water before noon to allow ample time for evaporation.

Rehydrate the Soil

Gradually infuse moisture into the soil, allowing it to permeate and revitalize the root system. Thorough saturation is the goal, evidenced by water gently seeping from the pot's drainage holes.