Here are the main food plants (there can be others) used by the species that we are seeing at the moment:

Orange Tip

Cuckoo-flower, Garlic mustard & other crucifers;

Large White

Brassicae (e.g. cabbage and brussel-sprouts), Garlic mustard & other crucifers, Nasturtium;

Small White

Brassicae (e.g. cabbage and brussel-sprouts), Garlic mustard & other crucifers, Nasturtium;

Green-veined White

Cuckoo-flower, Garlic mustard & other crucifers;

Brimstone

Buckthorn & Alder Buckthorn;

Speckled Wood

Grasses;

Red Admiral

Common Nettle;

Peacock

Common Nettle;

Small Tortoiseshell

Common Nettle;

Comma

Common Nettle, Hops, Elms;

Holly Blue

Holly (in spring) Ivy (in Summer), plus a range of other plants including Spindle, Pyracantha, Dogwoods, Snowberry, Wild liquorice;

There are photos for most of the stages on www.bedsbutterflies.org.uk but there are gaps for eggs of Peacock and Small Tortoiseshell that I'll be trying to fill myself.

The easiest eggs to find are for Orange Tip and Brimstone, but all of these can be found by discovering a female that is hopping from plant to plant, obviously not feeding on flowers. She is probably tasting through her feet if she is standing on the right food for her offspring, and when she eventually is she will then curve her abdomen around to emit the egg from the tip which is glued to the plant. Keep your eye on where she was and then move in for a macro photo once she has moved on.

The larvae are usually easier to find because they are bigger and cause obvious feeding damage to the plant. Some even feed communally on webs, such as Peacock and Small Tortoiseshell which makes these easier to spot.

The pupae are the hardest stage of all to find and most of my photos are from breeding-through at home. I have never found Orange Tip in the wild despite looking where there had been many larvae! See if you can do better than me. The pupae will begin to be formed in only 3-4 weeks from now as it takes only that long to go from egg to pupa.

Perhaps you'd like to post pictures of your discoveries on Facebook to either "Bedfordshire Nature Spotters" (https://www.facebook.com/groups/563246410375084) or "Wild About Beds" (https://www.facebook.com/groups/248658738538249/) and don't forget to submit the records using either Adnoto (https://www.bnhs.co.uk/adnoto/forms/butterflies.php) or one of the iRecord family of Apps/websites e.g. (https://www.brc.ac.uk/irecord/enter-casual-record).

I hope you enjoy searching.

Don't become too engrossed though - remember to keep 2m distance from any humans you discover!